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Human bladder infected with Schistosoma haematobium.
Eggs are widely scattered in the tissue. H&E, X100.

Duk-Young Min


Human bladder infected with Schistosoma haematobium. Eggs and extensively infiltrated eosinophils are seen. H&E, X400.

Duk-Young Min


Cutaneous nodule with Onchocerca volvulus in human. H&E, X40.

Duk-Young Min



Yong Suk Ryang



Yong Suk Ryang


























Pseudogobio esocinus, a freshwater fish, caught at Keum-gang (river) in Keumsan-gun, Chungcheongnam-do. The second intermediate host of trematodes.

Sung-Jong Hong


Pediculus humanus var. capitis, male.

Sung-Jong Hong


Trophozoites of Acanthamoeba sp. showing spinelike pseudopods (Giemsa stain, 1000x). A. Trophozoites of Acanthamoeba sp. in culture medium showing vacuole and spinelike pseudopods (1000x).

DY Min/MH Ahn/JS Ryu


Trophozoite of Trichomonas vaginalis showing a nucleus, axostyle and 4 anterior flagella (B, Giemsa stain, 1000x). Cultured trophozoites show flagella and vacuoles (A).

DY Min/MH Ahn/JS Ryu


Procerovum varium collected from a cat.

Woon-Mok Sohn


P. varium collected from a cat.

Woon-Mok Sohn


P. varium collected from a cat. Semichon's acetocarmine stained.

Woon-Mok Sohn


Procerovum varium collected from a cat. Semichon's acetocarmine stained.

Woon-Mok Sohn


Schematic drawing of Procerovum varium.

Woon-Mok Sohn


Metacercariae of Metagonimus sp. in the scale of Z. platypus.

Woon-Mok Sohn


Metacercaria of Metagonimus sp. from a Z. platypus.

Woon-Mok Sohn


Metacercaria of Metagonimus sp. from a Z. platypus.

Woon-Mok Sohn


Metacercaria of Metagonimus sp. from a dark chub, Zacco temminckii.

Woon-Mok Sohn


Metacercaria of Metagonimus sp. a crucian carp, Carassius auratus.

Woon-Mok Sohn


Excysted metacercaria of Metagonimus sp. from a Carassius auratus.

Woon-Mok Sohn


Metagonimus sp. collected from a cat.

Woon-Mok Sohn


Metagonimus sp. collected from a cat. Semichon's acetocarmine stained.

Woon-Mok Sohn


M. takahashii recovered from a hamster, which was experimentally infected with metacercariae. Semichon's acetocarmine stained.

Woon-Mok Sohn


M. takahashii from human. Semichon's acetocarmine stained.

Woon-Mok Sohn


Cryptocotyle sp. collected from a cat. Semichon's acetocarmine stained.

Woon-Mok Sohn


Cryptocotyle sp. collected from a cat. Semichon's acetocarmine stained.

Woon-Mok Sohn


Metacercaria of Massaliatrema misgurni from a loach imported from China.

Woon-Mok Sohn


Excysted metacercaria of Massaliatrema misgurni from a Chinese loach.

Woon-Mok Sohn


Massaliatrema misgurni recovered from a chick, which was experimentally infected with metacercariae. Semichon's acetocarmine stained.

Woon-Mok Sohn


Schematic drawing of Massaliatrema misgurni.

Woon-Mok Sohn


SEM view of Massaliatrema misgurni from a chick, which was experimentally infected with metacercariae.

Woon-Mok Sohn


Metacercaria of Parvatrema chaii isolated from a Mactra veneriformis.

Woon-Mok Sohn


Parvatrema chaii recovered from a mouse, which was experimentally infected with metacercariae. Semichon's acetocarmine stained.

Woon-Mok Sohn


Unidentified 24 collar spined-echinostome metacercaria isolated from Pseudorasbora parva.

Woon-Mok Sohn


Unidentified echinostome metacercaria isolated from P. parva.

Woon-Mok Sohn


Metacercaria of Diplostomum sp. isolated from the eye of P. parva.

Woon-Mok Sohn


Metacercaria of Diplostomum sp. isolated from the eye of P. parva. Semichon's acetocarmine stained.

Woon-Mok Sohn


Metacercariae of Clonorchis sinensis (smaller and thinner cyst wall) and Metorchis orientalis collected from Pseudorasbora parva.

Woon-Mok Sohn


Metacercaria of M. orientalis collected from P. parva.

Woon-Mok Sohn


Excysted metacercaria of M. orientalis collected from Pseudorasbora parva.

Woon-Mok Sohn


M. orientalis recovered from an experimantally infected chick. Semichon's acetocarmine stained.

Woon-Mok Sohn


M. orientalis recovered from an experimentally infected chick. Semichon's acetocarmine stained.

Woon-Mok Sohn


Metacercaria of Metorchis taiwanensis collected from P. parva.

Woon-Mok Sohn


M. taiwanensis recovered from an experimentally infected chick. Semichon's acetocarmine stained.

Woon-Mok Sohn


Metacercaria of Plagiorchis sp. isolated from a dragonfly.

Woon-Mok Sohn


Metacercaria of Plagiorchis sp. isolated from an experimental tadpole.

Woon-Mok Sohn


Excysted metacercaria of Plagiorchis sp. isolated from an experimental tadpole.

Woon-Mok Sohn


Plagiorchis sp. collected from a naturally infected cat. Semichon's acetocarmine stained.

Woon-Mok Sohn


Metacercaria of Macroorchis spinulosus isolated from a crayfish.

Woon-Mok Sohn


Macroorchis spinulosus recovered from an experimentally infected rat.

Woon-Mok Sohn


Macroorchis spinulosus recovered from an experimentally infected rat. Semichon's acetocarmine stained.

Woon-Mok Sohn


Egg of heterophyid fluke from a cat.

Woon-Mok Sohn


Egg of heterophyid fluke from a cat.

Woon-Mok Sohn


Egg of Cyathocotyle orienralis from a chick, which was experimentally infected.

Woon-Mok Sohn


A plerocercoid of Sprimetra erinacei isolated from an experimental tadpole at 5 days after infection.

Woon-Mok Sohn


Odontobutis platycephala, Korean dark sleeper.

Woon-Mok Sohn


Bluegill.

Woon-Mok Sohn


Zacco platypus (pale chub), a second intermediate host of Metagonimus miyatai.

Woon-Mok Sohn


Cerithideopsilla sp., creeper.

Woon-Mok Sohn


Cerithideopsilla sp., creeper.

Woon-Mok Sohn


Mactra veneriformis (surf clam), the intemediate host of Acanthoparyphium tyosenense.

Woon-Mok Sohn


Rana rugosa, a final host of Diplorchis ranae.

Woon-Mok Sohn


Macrophthalmus japonious.

Woon-Mok Sohn


Metacercaria of Gynaecotyla squatarole from Macrophthalmus japonious.

Woon-Mok Sohn


Excysted metacercaria of Gynaecotyla squatarole from Macrophthalmus japonious.

Woon-Mok Sohn


Adult Gynaecotyla squatarole from an experimental mouse.

Woon-Mok Sohn


Drawing of adult Gynaecotyla squatarole (Yamaguti, 1934) Yamaguti, 1939.

Woon-Mok Sohn


Probolocoryphe asadai metacercaria from Macrophthalmus japonious.

Woon-Mok Sohn


Excysted metacercaria of Probolocoryphe asadai from Macrophthalmus japonious.

Woon-Mok Sohn


Adult Probolocoryphe asadai from an experimental mouse.

Woon-Mok Sohn


Drawing of adult Probolocoryphe asadai (Otagaki, 1958).

Woon-Mok Sohn


Spelophallus metacercaria from Macrophthalmus japonious.

Woon-Mok Sohn


Excysted metacercaria of Spelophallus sp. from Macrophthalmus japonious.

Woon-Mok Sohn


Adult Spelophallus sp. from an experimental mouse.

Woon-Mok Sohn


Drawing of adult Spelophallus sp.

Woon-Mok Sohn


Metacercaria of Spelophallus sp.

Woon-Mok Sohn


Stephanostomum bicoronatum metacercaria from a goby.

Woon-Mok Sohn


Excysted metacercaria of Stephanostomum bicoronatum.

Woon-Mok Sohn


Excysted metacercaria of Stephanostomum bicoronatum.

Woon-Mok Sohn


Prosorhynchus uniporus metacercaria from goby.

Woon-Mok Sohn


Pseudogalactosoma macrostoma metacercaria from goby.

Woon-Mok Sohn


Bucephalopsis ovata from a naturally infected catfish.

Woon-Mok Sohn

.

See Visceral Leishmania.

See Visceral Leishmania.

See Cutaneous Leishmania.

Scientific name. Necator americanus/Ancylostoma duodenale

Scientific name. Leishmania donovani, Leishmania infantum, Leishmania chagasi

Scientific name. Leishmania tropica, Leishmania major, Leishmania aethiopica

Scientific name. Trichinella spiralis, T. pseudospiralis, T. nativa, T. nelsoni, T. britovi, T. murrelli

Scientific name. Gnathostoma spinigerum, G. hispidum, G. doloresi, G. nipponicum

House dust mites

Scientific name. Anisakis simplex, A. physeteris, Pseudoterranova decipiens

Common name. Bancroft's filaria

Common name. Malayan filaria

Common name.

Common name. Oriental liver fluke, Chinese liver fluke

Common name. Cattle liver fluke

Common name. Dwarf tapeworm

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Common name. Roundworm

Common name. Lung fluke

Common name. broad tapeworm, fish tapeworm

Common name. convoluted filaria

.

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Common name. Dog tapeworm, cucumber tapeworm

Common name. Oriental eyeworm

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Common name. pinworm, seat worm

See Hookworms.

See Hookworms.

Common name. New World Hookworm/Old World Hookworm

Common name. the hydatid worm

Common name. The hydatid worm

Common name. Lancet liver fluke

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.

Common name. pubic louse, crab louse

See Visceral Leishmania.

See Cutaneous Leishmania.

See Cutaneous Leishmania.

See Trichinella species.

See Gnathostomes.

See Gnathostomes.

See Gnathostomes.

See House dust mites.

See House dust mites.

See Anisakis species.

See Anisakis species.

See Anisakis species.

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.

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.

See Metagonimus species.

See Metagonimus species.

See Metagonimus species.

Common name. Blood flukes

See Schistosoma species.

See Schistosoma species.

See Schistosoma species.

See Acanthamoeba species.

See Acanthamoeba species.

See Acanthamoeba species.

Disease. bancroftian filariasis

Disease. Malayan filariasis

Disease. trichostrongyliasis

Disease. Clonorchiasis

Disease. fascioliasis

Disease. hymenolepiasis

Disease. falciparum malaria, malignant tertian malaria

Disease. malariae malaria, quartan malaria,

Disease. ovale malaria

Disease. vivax malaria, tertian malaria,

Disease. ascariasis, ascaris infection, roundworm infection

Disease. Paragonimiasis

Disease. diphyllobothriasis

Disease. onchocerciasis, river blindness

Disease. trichomoniasis

Disease. dipylidiasis

Disease. thelaziasis

Disease. amebiasis, amebic dysentery, amebic hepatitis

Disease. Gambian trypanosomiasis, Mid-African sleeping sickness

Disease. Rhodesian trypanosomiasis, East-African sleeping sickness

Disease. cryptosporidiosis

Disease. pneumocystosis, PCP (Pneumocystis carinii pneumonia)

Disease. Chagas' disease, American trypanosomiasis

Disease. enterobiasis

Disease. necatoriasis/ancylostomiasis

Disease. echinostomiasis

Disease. Hydatid disease, Hydatidosis, Unilocular hydatid disease

Disease. Hydatid disease, Hydatidosis, Alveolar (multilocular) hydatid disease

Disease. dicrocoeliasis

Disease. opisthorchiasis

Disease. euretremiasis

Disease. phthiriasis, pediculosis pubis

Disease. Kala-azar, visceral leishmaniasis

Disease. Oriental sore, Old world cutaneous leishmaniasis

Disease name. trichinosis

Disease name. Gnathostomiasis

Definition. Mites belonging to the Family Pyroglyphidae, which are living in house dusts

Important species. Dermatophagoides farinae (Df) and Dermatophagoides pteronyssinus (Dp) are the most important species

Disease. Anisakidosis

Disease. Heterophyiasis

Disease. Heterophyiasis

Disease. Heterophyiasis

Disease. Heterophyiasis

Disease. Gymnophalloidiasis

Disease. Neodiplostomiasis

Disease. Echinochasmiasis

Disease. Metagonimiasis

Disease. Schistosomiasis; schistosomal hematuria, vesical schistosomiasis, urinary bilharziasis (S. haematobium); intestinal bilharziasis, schistosomiasis mansoni (S. mansoni); Oriental schistosomiasis, Katayama disease, schistosomiasis japonica (S. japonicum)

Disease. Acanthamoebic infection, Acanthamoebic keratitis, Granulomatous amoebic encephalitis

Geographic distribution. Worldwide in temperate and tropic zone.

Geographic distribution. India, Pakistan, Thailand, China, the Philippines, New Guinea, Central Africa and Nile delta, South and Central America

Geographic distribution. The Philippines, Indonesia, Sri Lanka, Vietnam, Thailand, China, Malaysia and in specific parts of Korea.

Geographic distribution. Worldwide in temperate and tropic zone.

Geographic distribution. Japan, Korea, China, Taiwan, Armenia, etc.

Geographic distribution. China, Korea, Russia, Taiwan, Hong Kong, and Vietnam

Geographic distribution. Europe, Africa, Asia, Australia, South and Central America

Geographic distribution. Worldwide, but more frequent in hot countries. Portugal, Spain, Sicily, Egypt, Sudan, India, etc.

Geographic Distribution. Worldwide, usually restricted to tropical and subtropical areas and altitudes below 1,500 m. P. falciparum predominates in Africa, New Guinea, and Haiti

Geographic Distribution.orldwide, malaria usually restricted to tropical and subtropical areas and altitudes below 1,500 m. P. malariae is found in most endemic areas, especially throughout sub-Saharan Africa

Geographic Distribution. Worldwide, malaria usually restricted to tropical and subtropical areas and altitudes below 1,500 m. P. ovale is relatively unusual outside of Africa.

Geographic Distribution. Worldwide, malaria usually restricted to tropical and subtropical areas and altitudes below 1,500 m. P. vivax is more common in Central America and the Indian subcontinent

Geographic distribution. Worldwide. more than 150 countries around tropic, subtropic, and temperate areas.

Geographic distribution. The Genus Paragonimus composed of over 40 species. Human infections occur in restricted areas where local people consume improperly cooked freshwater crustaceans. Paragonimus westermani, a type species, causes inflammatory lung diseases in several Asian countries of Korea, Japan, China, Far-east of Russia, Taiwan, the Philippines, Malaysia, Indonesia, and India. P. miyazakii in Japan, P. skrjabini in China, P. heterotremus in Southeast Asia and in southern part of China, P. uterobilateralis and P. africanus in Africa, P. mexicanus in Latin America, and P. kellicotti in North America also invoke human infection. These species also invoke pleuropulmonary and subcutaneous infections.

Geographic distribution. The distribution of this worm is worldwide, especially in northern Italy, Switzerland, Germany, Baltic countries, Finland, Sweden, central Siberia, North America, northern Manchuria, Japan, Korea, and Chile.

Geographic distribution. Mostly in Subsaharan Africa, Yemen, Guatemala, Mexico, Venezuela, Ecuador, Colombia, and Brazil

Geographic distribution. Worldwide

Geographic distribution. Worldwide.

Geographic distribution. A cosmopolitan parasite of dogs and cats. Human cases have been reported in the European, the Latin American, the East Asian, the South African countries, and in the United States.

Geographic distribution. India, Burma, China, Korea, Japan, Russia, etc.

Geographic distribution. Worldwide in tropical and temperate zone

Geographic distribution. Tropical West and Central Africa

Geographic distribution. The disease is endemic among the cattle-raising tribes of East Africa. Present in Zimbabwe, Zambia, Malayi, Mozambique, Tanzania, and eastern Uganda.

Geographic distribution. Worldwide in temperate and tropical zone

Geographic distribution. Cosmopolitan over the world.

Geographic distribution. Endemic in 21 countries in the South and Central America.

Geographic distribution. cosmopolitan in cool and temperate zone.

Geographic distribution. Necator americanus : Southeast Asia, India, Sub-Saharan Africa and Tropical America. Ancylostoma duodenale : Northern India, Parkistan, China, Middle East and Northern Africa.

Geographic distribution. Korea, Japan, Taiwan, and Java

Geographic distribution. Worldwide in distribution. Most commonly found in sheep and cattle-raising countries.

Geographic distribution. Primarily in Europe, Asia, New Zealand, and South/North America.

Geographic distribution. Europe, Asia, North Africa, North America and South America

Geographic distribution. Endemic in Northeast Thailand, Laos, Kampuchea, etc.

Geographic distribution. Endemic in Russia and occurs mainly in Siberia, Ukraine, and Kazazhstan.

Geographic distribution. China, Korea, Japan, Hong Kong, South America, etc.

Geographic distribution. India, China, Bangladesh, Middle East, Mediterranean countries, Tropical Africa, Central and South American countries.

Geographic distribution. India, China, Bangladesh, Middle East, Mediterranean countries, Tropical Africa, South American countries.

Geographic distribution.
Trichinella spiralis: cosmopolitan (mainly temperate zones)
T. pseudospiralis: cosmopolitan (mainly temperate zones)
T. nativa: arctic and subartic regions
T. nelsoni: tropical Africa, northern Sahara
T. britovi: Europe, Africa (northern Sahara), northern Arabia, northern Asia, and central Asia
T. murrelli: U.S.A

Geographic distribution.
G. spinigerum: Palestine, India, Bangladesh, Burma, Thailand, Laos, Cambodia, Viet Nam, Malaysia, Indonesia, Philippines, China, Japan, Australia, Equador
G. hispidum: Turkestan, Hungary, Austria, Germany, Romania, Thailand, Viet Nam, Malaysia, Philippines, Korea, Taiwan and China
G. doloresi: India, Burma, Thailand, Viet Nam, Singapore, Philippines, Taiwan, Japan and New Guinea
G. nipponicum: Japan

Geographical distribution. Worldwide in temperate and tropical zone. Df is more dominant in less humid areas, whereas Dp is found mostly in high humid areas; in general the dominant species is Df in North America and Dp in European countries.

Geographic distribution. Occurs wherever raw fishes are consumed. Japan, Netherlands, Germany, France, Korea, Hawaii, Alaska and West Coast states of USA.

Geographic distribution. Korea, Japan and China

Geographic distribution. Asia-Pacific countries: Philippines, Hawaii, Japan, Thailand and Korea.

Geographic distribution. Korea and Japan

Geographic distribution. Korea and Australia

Geographic distribution. Korea

Geographic distribution. Korea and China

Geographic distribution. Human cases were found from Far-Eastern countries including Korea, Japan and China.

Geographic distribution. Korea, Japan, China, Taiwan, and Russia

Geographic distribution. Schistosoma mansoni is found from the areas of South America and the Caribbean, Africa, and the Middle East; S. haematobium, from Africa and the Middle East; and S. japonicum from the Eastern countries including China, Japan, Philippines, Indonesia and Malaysia.

Geographic distribution. Worldwide distribution

Infection rate. Less than 10% through out the world.

Infection rate. Not clear.

...

Infection rate. The total number of persons infected worldwide is estimated more than 20 million.

Infection rate. Human infection is not common, but occurring worldwidely.

Infection rate. The incidence of infection in man ranges from less than 1 to 28%.

Infection rate. WHO estimates that yearly 300-500 million cases of malaria occur and more than 1 million people die of malaria. P. falciparum and P. vivax are most common

Infection rate. WHO estimates that yearly 300-500 million cases of malaria occur and more than 1 million people die of malaria. P. malariae is much less common than the other species.

Infection rate. WHO estimates that yearly 300-500 million cases of malaria occur and more than 1 million people die of malaria. P. ovale, where it is found, comprises <1% of isolates.

Infection rate. WHO estimates that yearly 300-500 million cases of malaria occur and more than 1 million people die of malaria. P. vivax and P. falciparum are the most common.

Infection rate. World prevalence range from around 650 million to 1,000 million.

Infection rate. The total number of persons infected worldwide is not determined. Annally about 200 cases and 500 cases are sporadically detected in Japan and Korea, respectively. The infection is also reported to be high in the Philippines and India.

Infection rate. The case reports or increased outbreaks have been reported in the above countries.

Infection rate. About 20 to 40 million people are infected.

Infection rate. About 9.9 to 41.4% in women.

Infection rate. About 6% of the world population

Infection rate. D. caninum is common in dogs and cats, children are infected occasionally.

Infection rate. Thelaziasis is thought to be sporadically occurring throughout the world.

Infection rate. The actual incidence of amebiasis in the worldwide remains unknown. Survey indicate that the infection rates vary from 0.2 to 50%, being directly correlated with sanitary conditions.

Infection rate. The incidence of Gambian trypanosomiasis is usually less than 3% in endemic areas.

Infection rate. The incidence of Rhodesian trypanosomiasis is lower and epidemics are less frequent than in the Gambian disease.

Infection rate. Cryptosporidium parvum is ubiquitous, infecting most mammals, and is highly infectious. Thus everyone is at some risk of acquiring cryptosporidiosis. Prevalence rates of cryptosporidiosis in diarrheal illness range from a few per cent in cooler, more developed countries (0.1-2% overall), to 0.5-10% in warmer, less developed countries. Recent data suggest that 3-4% of AIDS patients in the USA and Europe will become infected with cryptosporidiosis during their symptomatic period. In the developing contries the equivalent numbers are much higher up to 50% in hospital patients with AIDS.

Infection rate. Several ten thousands of new patients appear annually in the world.

Infection rate. 100 million people are at risk, which is about 25% of the population of Latin America. 16-18 million people are infected and 50,000 die annually.

Infection rate. Sporadically occurring cases in man are documented in some Asian countries.

Infection rate. Less than 20 cases of human infections (including an indigenous case) were reported in Korea. Recent infection rate of livestocks is not available.

Infection rate. Human infection with alveolar hydatid cyst is rare.

Infection rate. The fluke is primarily a parasite of ruminants, but is occasionally also found in man.

Infection rate. Up to 7 million persons may be infected. The overall prevalence is about 35%; but in some areas, it is over 90%.

Infection rate. Prevalence rates up to 85% had been reported in certain areas of the USSR.

Infection rate. E. pacreaticum is a common parasite of pancreatic (or rarely bile) ducts of herbivorous mammals, i.e., cattle, sheeps, goats, monkeys, and camels.

Infection rate. Thousands of new patients appear annually in endemic areas.

Infection rate. Several ten thousands of new patients appear annually in those endemic areas.

Infection rate. Infection status can not be estimated. Sporadic outbreaks have been reported in all over the world. Many outbreaks have recently occurred in China, Romania, Argentina, Russia, Serbia, Bulgaria, Croatia, Lebanon and France. In Korea, two times of epidemics were recently occurred with total 8 persons of infection with T. spiralis. The source of infections were the raw flesh of wild raccoon dogs and boars.

Infection rate. Infection status can not be correctly estimated because the gnathostomes are tissue invading nematodes; their infections are nto easily diagnosed. In Korea, one case of Thai woman infected with G. spinigerum was reported in 1988, and the larvae of G. hispidum wre detected in a snake host, Agkistrodon brevicaudus.

Infection rate. Unknown in worldwide.

Infection rate. Human cases were found only from Korea. Some inhabitants revealed 72% of prevalence in an endemic area.

Infection rate. Human infections are found only from Korea and China. Prevalence is unknown.

Infection rate. Prevalence in human is not known well.

Infection rate. Unknown in worldwide.

Infection rate. It is a parasitic disease with a wide range of clinical manifestations that affects more than 200 million people in 77 countries. Only 10% of infected individuals have severe clinical symptoms and this still represents 20 millions of seriously ill people worldwide.

Infection rate. Acanthamoebic keratitis known to be closely associated with contact lens wearing was reported more commonly in industrialized countries than developing or under-developed countries. The number of case report has been rapidly increasing in last decade. Granulomatous amoebic encephalitis occurs rarely and small number of cases were reported.

Life cycle. The Culex, Aedes, and Anopheles species of mosquitoes serve as the intermediate host and vectors of W. bancrofti. In the human host the adult worms take up residence in the lymphatics, where they lay their microfilariae. The microfilariae liberated in the lymph, find their way into the thoracic duct and then to the blood circulation.

Life cycle. The Anopheles, Aedes, Mansonia and Armigeres species of mosquitoes serve as the intermediate host and vectors of B. malayi. All other respects of the life cycle are basically the same as those of W. bancrofti.

Life cycle. Same as that of E. histolytica.

Life cycle. The adult worms develop in man without lung migration. The third larval stages, which are capable of invasion when ingested orally, establish themselves directly in the small intestinal wall (duodenum and jejunum) and grow to sexually mature worms.

Life cycle. The adult worms live in the bile ducts of the final hosts. The eggs pass out with the feces and hatch to miracidia when ingested by suitable freshwater snails (first intermediate hosts). Stages of sporocyst, redia, and cercaria undergo in snails, i.e., Parafossarulus manchouricus. Mature cercariae hatch into the water and infect freshwater fish of Family Cyprinidae (second intermediate hosts) to make encysted metacercariae in the muscle. The final hosts get infected by ingesting raw or undercooked fish. The important final hosts are humans, dogs, cats, pigs, and rodents.

Life cycle. The adult worms live in the bile ducts of the final hosts. The eggs are passed into the environment with the feces. The miracidia hatch in freshwater and infect snails (first intermediate hosts). Stages of sporocyst, redia, and cercaria undergo in snails. Mature cercariae encyst on water vegitation, i.e., watercress to make metacercariae. The final hosts are infected by ingestion of undercooked aquatic vegetation or raw cattle liver. The important final hosts are cattle, sheeps and goats.

Life cycle. H.nana can develop directly in the small intestine of the definitive hosts as well as in an intermediate hosts (insects). If larva-bearing eggs enter the human gastrointestinal tract, the oncospheres are released into the duodenum and attatch to the villi, where each develops into a cysticercoid. Within 2-3 weeks, the cysticercoid develops into a tapeworm. It is a common parasite of the house mice and is found in human, especially in children.

Life cycle. An infected female Anopheles mosquito inoculates sporozoites into the human during a blood meal. Sporozoites infect liver cells and mature into schizonts, which release merozoites (exo-erythrocytic schizogony). The merozoites infect red blood cells. The ring stage trophozoites mature into schizonts, which rupture releasing merozoites (erythrocytic schizogony). Some parasites differentiate into sexual erythrocytic stages (gametocytes). The gametocytes are ingested by an Anopheles mosquito during a blood meal. The microgametes penetrate the macrogametes generating zygotes in the stomach. The zygotes become ookinetes and invade the midgut wall where they develop into oocysts. The oocysts release sporozoites, which make their way to the mosquito's salivary glands (sporogonic cycle).

Life cycle. A malaria-infected female Anopheles mosquito inoculates sporozoites into the human host during a blood meal. Sporozoites infect liver cells and mature into schizonts, which rupture and release merozoites (exo-erythrocytic schizogony). The merozoites infect red blood cells. The ring stage trophozoites mature into schizonts, which rupture releasing merozoites (erythrocytic schizogony). Some parasites differentiate into sexual erythrocytic stages (gametocytes). The gametocytes are ingested by an Anopheles mosquito during a blood meal. The microgametes penetrate the macrogametes generating zygotes in the mosquito's stomach. The zygotes become ookinetes and invade the midgut wall where they develop into oocysts. The oocysts grow, rupture, and release sporozoites, which make their way to the mosquito's salivary glands (sporogonic cycle).

Life cycle. A malaria-infected female Anopheles mosquito inoculates sporozoites into the human host during a blood meal. Sporozoites infect liver cells and mature into schizonts, which rupture and release merozoites (exo-erythrocytic schizogony). In P. vivax and P. ovale a dormant stage (hypnozoites) can persist in the liver for weeks, or even years. The merozoites infect red blood cells. The ring stage trophozoites mature into schizonts, which rupture releasing merozoites (erythrocytic schizogony). Some parasites differentiate into sexual erythrocytic stages (gametocytes). The gametocytes are ingested by an Anopheles mosquito during a blood meal. The microgametes penetrate the macrogametes generating zygotes in the mosquito's stomach. The zygotes become ookinetes and invade the midgut wall where they develop into oocysts. The oocysts grow, rupture, and release sporozoites, which make their way to the mosquito's salivary glands (sporogonic cycle).

Life cycle. A malaria-infected female Anopheles mosquito inoculates sporozoites into the human host during a blood meal. Sporozoites infect liver cells and mature into schizonts, which rupture and release merozoites (exo-erythrocytic schizogony). In P. vivax and P. ovale a dormant stage (hypnozoites) can persist in the liver for weeks, or even years. The merozoites infect red blood cells. The ring stage trophozoites mature into schizonts, which rupture releasing merozoites (erythrocytic schizogony). Some parasites differentiate into sexual erythrocytic stages (gametocytes). The gametocytes are ingested by an Anopheles mosquito during a blood meal. The microgametes penetrate the macrogametes generating zygotes in the mosquito's stomach. The zygotes become ookinetes and invade the midgut wall where they develop into oocysts. The oocysts grow, rupture, and release sporozoites, which make their way to the mosquito's salivary glands (sporogonic cycle).

Life cycle. Ascaris eggs are unsegmented when passed; under favorable conditions they require a period of about 2 or 3 weeks outside the host to develop to the infective stage. Excessive heat and dryness soon kill them, but they remain viable in moist soil for long periods. When fully embryonated eggs are swallowed, they hatch in the duodenum and then undergo an extraordinary migration through the body before returning to settle down in the intestine and grow to adulthood.

Life cycle. Paragonimus is a typical digenean trematode of carnivorous mammals. Large immature eggs are spread throughout in stool, and mature to miracidia in freshwater. They infect snails in which they undergo three generations of asexual reproduction (redia, daughter redia, and cercaria). Microcercous cercariae are released into water where they infect freshwater crustaceans (crabs and crayfish). As encysted, they become metacercariae. The metacercariae are infective to definitive hosts. They also infect paratenic (transport) hosts. Carnivorous mammals are the most important definitive hosts. In case of P. westermani, rodent and boar are known to be transport hosts. The metacercariae excyst in the duodenum, penetrate the intestinal wall, and stay in the peritoneal cavity for a while. The parasites finally arrive to the lung in which they become adult worms approximately 8-10 weeks after metacercarial infection. They liberate eggs in sputum and stool. The worms are thought to thrive approximately 5 years in men. Main habitat of the parasite in the definitive hosts is the bronchiolar lumen and peribronchial tissues.

Life cycle. Infection with the adult worm is acquired by the ingestion of raw, poorly cooked, or pickled salmon, trout, perch, pike, white fish, grayling, ruff, eel, etc., harboring the plerocercoid larvae. After five or six weeks, the larva matures to the adult worm. Both eggs and proglottids are passed in the stool. The eggs develop in 2 weeks, and hatch to become ciliated coracidium larvae, and are ingested by the first intermediate host, the copepod. The copepods, containing the procercoid larvae, are ingested by fish, the second intermediate host, contains the plerocercoid larvae.

Life cycle. Infection comes from the bites of female blackflies of the genus Simulium, which transmit the infective larvae of the parasite. Over 10 to 20 months these larvae grow to adult worms, which live for up to 15 years tangled together in fibrous nodules under the skin. The adult females produce a continuous supply of live embryos or microfilariae. Skin microfilariae ingested by biting Simulium develop to infective larvae in seven to ten days and can be transmitted to a new host.

Life cycle. Normal habitats of T. vaginalis are the human vagina and prostate gland. T. vaginalis multiplies by longitudinal binary fission. There is no cystic stage.

Life cycle. This parasite lives in the cecum and colon of humans, chimpanzees, orangutans, monkeys, and pigs. The trophozoites mutiply by binary fission. Transmission occurs by ingestion of cysts. Fecal contamination of drinking water is major route of transmission.

Life cycle. When the eggs are ingested by intermediate host-the larvae of the flea or the dog louse-the oncospheres hatch, penetrate into the gut, and develop into cysticercoids in about 2 weeks. When the infected flea or louse is ingested by a final host, i.e., dogs, foxes, jackals, hyenas, cats, and humans, the cysticercoids mature into adults in the small intestine in about 20 days. The eggs and gravid proglottids are expelled in the feces.

Life cycle. The adult worm is parasitic in the conjunctival sac of a final host, and it liberates viviparous larvae. These larvae are equivalent to the 1st stage larva. When they are swallowed by fly, They take off the sheaths in the digestive tract, go through the wall, invade the ovary or testis, where They become thin, 2-2.5 mm long 3rd stage larvae after two molts. They are the infective larvae. When the fly lick tears in the eyes of a final host, the larvae enter the conjunctival sac, and become adults in a month after two molts. The final hosts are mainly dogs and cats, and occasionally rabbits, monkeys, foxes, and humans. The intermediate hosts are insects. In Japan, species of Genus Amiota have been identified.

Life cycle. Human is the principal host and the source of infection. The infective cysts pass out through the feces, and are immediately infective. Cyst-contaminated food or water cause infections. Excystment takes place in the lower part of the small intestine. The immature amebas move downward to the large intestine, where they establish a site of infection. Reproduction occurs by binary fission.

Life cycle. The main vertebrate host is human. The principal invertebrate hosts are tsetse flies of the Genus Glossina genus. T. gambiense is transmitted to humans by biting of an infected tsetse fly after the cyclic development of the parasite.

Life cycle. Antelopes and possibly other wild game and domesticated cattle are reservoir hosts. The main insect vectors are the woodland tsetse flies of Glossina spp. T. rhodesiense is transmitted from animals to humans by the bite of an infected tsetse fly.

Life cycle. Genus cryptosporidium has a wide range of hosts such as humans, mammals, birds, reptiles, and fishes. Oocyst-contaminated water, soil, and vegetables cause infections. Sporozoites released from oocyst are attached intestinal epithelial cells after excystation and develop into trophozoite. Trophozoite undergo asexual life cycle (merogony) and then sexual multiplication. Oocysts are produced and excreted through the feces after fertilization of macrogamete and microgamete. Thin walled oocysts could induce autoinfection by being excysted in intestinal lumen.

Life cycle. The organism is transmitted via air. It has two stages, cystic and trophic form. In the lungs, the intracystic bodies grow to trophic forms and proliferate on the surface of the pneumocytes and in the alveolar cavity only in the immunocompromised humans. Some of the trophic forms may grow to cystic forms which have 8 intracystic bodies and cell wall. The intracystic bodies continue to grow as trophic forms and/or cystic forms. The cystic forms may be transmitted between humans.

Life cycle. When a kissing bug bites a person, it often leaves trypanosome-containing feces on the skin. Rubbing the bite site can pass the parasites into the skin, eyes, or mucus membranes, where the trypanosomes infect multiple cell types and reproduce. As the parasites increase in number, they rupture their host cells and spread through the blood to different tissues, with the muscles of the heart their primary target.

Transmission. 1) Through the bite of an infected triatomine insect (a blood-sucking, predatory bug of the Reduviidae family); 2) By transfusion of infected blood or organ transplants; 3) During pregnancy or at delivery, an infected mother can pass on the disease to her baby.

Life cycle. Human is the only known host of E. vermicularis. The usual habitat is the colon. Pinworm infection in human is initiated by the ingestion of the infective eggs, which hatch in the intestine, where they develop into the adult worms. In gravid females, almost of the entire body is filled with the eggs. The female worms migrate down to the colon and out of the anus, where the eggs are deposited on the perianal and perineal skin. Occasionally, the female worm migrates into the vagina.

Life cycle. Humans are infected with hookworm when third-stage filariform larvae in soil. They penetrate through the skin, particularly into areas such as unprotected feet. Once infected, the filariform larvae migrate into blood circulation. They break out of the pulmonary blood vessels into alveoli, then crawl up the trachea and are swallowed with saliva to re-enter the intestinal tract. They attach themselves to the mucous membrane of the small intestine to mature into adults.

Life cycle. Several fresh water snails, i.e., Hippeutis cantori, Segmentina hemispaerula and Austropeplea ollula, have been known as the first intermediate hosts. Several freshwater snail species, i.e., H. cantori, Radix auricularia coreana, Physa acuta, Cipangopaludina chinensis malleata, S. hemisperula, A. ollula, and Corbicula fluminea were also reported as the second molluscan intermediate hosts. Other second intermediate hosts include a loach, Misgurnus anguillicaudatus, and tadpole of Rana nicromaculata. Rats and dogs are found to be the natural definitive hosts. Humans can be infected by eating raw snails and loaches.

Life cycle. Human harbors the larval forms only. The adult worms infect the intestine of dog or caniids. When the eggs are ingested by the intermediate hosts, i.e., sheeps, domestic animals, or humans, embryos are hatched out in the duodenum, spread over the whole body to form hydatid cysts. The fully developed hydatids are capable of growing into adult worms in the definitive hosts.

Life cycle. Foxes, dogs, and cats are the definitive hosts. The hydatid cysts develop in several species of small rodents. The life cycle is similar to that of E. granulosus.

Life cycle. Embryonated eggs passed in the feces are ingested by land snails, in which they undergo a developmental cycle. Cercariae are liberated from the snails during rainy periods and become massed in slime-balls shed on vegetation as the snail crawls. These slime-balls, each of which contains a large number of cercariae, are eaten by ants. In this host, the cercariae become encysted to form metacercariae. For humans to acquire this disease, they must ingest an infected ant.

Life cycle. The adult worms live in the distal biliary duct or, sometimes, in the gallbladder. Eggs are released into the bile and passed to feces. Within the snails (first intermediate host), the miracidia hatch and develop sporocysts, rediae, and cercariae. Mature cercariae penetrate the muscle of susceptible freshwater fishes (secondary intermediate host) to develop into metacercariae. Consumption of infected fish is the source of infection for the definitive hosts: humans or fish-eating mammals.

Life cycle. Similar to O. viverrini and C. sinensis. It lives mainly in the bile duct, gallbladder and pancreatic duct of mammalian hosts. The organism enters the human host by consumption of raw fishes.

Life cycle. The adult flukes live in the pancreatic passages of the herbivores. Eggs are passed in the feces and ingested by land snail, which is the first intermediate host(snail). The cercariae develop into infective metacercariae only if ingested by grasshoppers, the second intermediate host. The life cycle is completed when the infected insects are eaten by grazing herbivores. The metacercariae excyst and migrate to the pancreatic passage, where they develop into adults. Humans become infected when they accidentally swallow infected grasshoppers.

Life cycle. Almost exclusively a parasite of man. Infestation is usually through sexual intercourse, but it can arise from infested clothing or bedding. P. pubis dwell primarily in the pubic region, but it may also be found in the axilla, beard, mustache, eyebrows, eyelashes, and chest. The life cycle, from egg laying to formation of the adult, is about 17-25 days. The female lay about 30 eggs during her life. The eggs (nits) are cemented to hair, and hatch within 6 to 8 days. The nymph undergoes three molts within two weeks. The life span of the adult is about 1 month.

Life cycle. The dog is the reservoir host and the vector is the sandfly (Subfamily: Phlebotominae). In mammalian hosts, amastigotes proliferate in the cytoplasm of mononuclear phagocytic cells of the viscera. When a female sandfly sucks blood of the infected dogs, the amastigotes enter into the vector and transform to promastigotes. As the promastigote-carrying sandflies suck blood of dogs or humans, the promastigotes are introduced into the new hosts. They are transformed to amastigotes and invade the phagocytic cells and proliferate. Human hosts are infected by sandfly- biting.

Life cycle. Rodents are the reservoir hosts; and vectors are the sandfly (Phlebotomus spp.). In rodents, amastigotes proliferate in the cytoplasm of mononuclear phagocytic cells of the viscera or skin. When a female sandfly vector sucks blood of the infected rodents, the amastigotes enter into the vector and transform as promastigotes. As the promastigote-carrying sandflies bite rodents or humans, the promastigotes are introduced into the new hosts. They are transformed to amastigotes and invade the phagocytic cells to proliferate. Human host is infected by sandfly-biting.

Life cycle. When the meat harboring the infective-stage larvae are ingested, the larvae excyst in the stomach or duodenum to invade the mucosal epithelium of small intestine. They then rapidly develop through the 4-larval stages, and mature in second day of infection. The adult worms live intracellularly within the superficial enterocytes of small intestine. After mating, females are inseminated, and begin to produce eggs that develop into minute larvae in the uterus. The larvae come of out the uterus, migrate into the blood stream via intestinal lymphatics or mesentric venules, and finally reach the striated muscles. They become encapsulated within the muscle fibers with exception those of T. pseudospiralis.

Life cycle. The adult worms live in the stomach or esophagus of the final hosts. The eggs pass out with the feces, cleave and embryonate in the water in appropriate temperature. The second stage larvae, after molt in embrynoated eggs, are hatched and swim actively in the water, and are ingested by fresh water copepods, i.e., Mesocyslops leuckarti, Eucyclops serrulatus, Cyclops strenuus and C. vicinus. The larvae take off the sheath in the digestive tract of the copepod and migrate to the body cavity, to become an early third-stage larvae after the second molt. When the copepods are eaten by tadpoles or fishes (the second intermediate host), the early third-stage larvae in the digestive tract of the second intermediate hosts enter the muscle, and grow into the advanced third-stage larvae. On the other hand, some kinds of animals other than final hosts play a role of paratenic hosts, which ingest the second intermediate hosts holding the larvae. The final hosts get infection by ingesting raw or undercooked intermediate or paratenic hosts. The important final hosts are dogs and cats (G. spinigerum), pigs and wild pigs (G. hispidum and G. doloresi), and weasels (G. nipponicum).

Life cycle. They develop through the stages of egg, larva, the first nymph, the second nymph, and adult. It takes a month in average to develop from eggs to adults, eating micro-organic materials. Their longevity is about 2 months.

Life cycle. The principle hosts of Anisakis are dolphins, porpoises, and whales; those of Pseudoterranova are seals, fur seals, walrus and sea lions. Eggs (40×50 ㎛) are discharged with the feces, and hatch in the cold water. L2 larvae are eaten by krill and develop into L3 larva. L3 larvae are transferred by the predatory food chain. The life cycle is completed when the infected fishes or squids are eaten by marine mammals, Humans are accidental or unsuitable host, so no maturation takes place. Herring, salmon, common mackerel, cod, conger eel and squid can transmit Anisakis, whereas cod, halibut, flatfish, and red snapper can transmit Pseudoterranova infection.

Life cycle. The second intermediate hosts are the perch, goby, shad (Clupanodon punctatus) and sweetfish (Plecoglossus altivelis). Domestic cats, ducks, and sea-gulls were reported to be the natural definitive hosts. Human infections were reported.

Life cycle. The first intermediate hosts are brackish water snails such as Stenomelania newcombi or Thiara granifera; the second intermediate host is the mullet.

Life cycle. The first intermediate host, snail, is Cerithidea sp. or Tympanotonus sp. The second intermediate hosts are the mullet or goby (Acanthogobius flavimanus). Natural infection of the domestic cats was reported.

Life cycle. The first intermediate hosts are brackish water gastropods, and the second intermediate hosts are various species of brackish water fishes, i.e., mullets, gobies, leather-jackets, pipefishes, and toadfishes.

Life cycle. The first intermediate host is unknown, but the second intermediate host was confirmed as the oyster Crassostrea gigas. Man and the palearctic oystercatcher Haematopus ostralegus have been shown to be natural definitive hosts.

Life cycle. The first intermediate hosts are freshwater snails, Hippeutis cantori and Segmentina (Polypylis) hemisphaerula. The second intermediate hosts are tadpoles and frogs. House rat is the natural definitive host. Terrestrial snakes, such as the grass snake Rhabdophis tigrina are regarded as the paratenic host. Mice, rats, and guinea pigs have been found to be susceptible laboratory hosts.

Life cycle. The first intermediate hosts are Parafossarulus (Bulimus) striatulus japonicus, and P. manchouricus. The second intermediate hosts are at least 24 kinds of fresh or brackish water fishes such as Pseudorasbora parva, Plecoglossus altivelis, Zacco platypus, Carassius carassius and Acanthogobius flavimanus, as well as the tadpoles of Rana rugosa. Animal definitive hosts are various kinds of birds and mammals in nature: Gallus domesticus, Anas platyrhynchos var. domestica, Nycticorax nycticorax and Milvus migrans lineatus, and stray dogs.

Life cycle. The first intermediate hosts are fresh water snails: Semisulcospira coreana or S. libertina (M. yokogawai), S. coreana or Koreanomelania nodifila (M. takahashii), and S. globus (M. miyatai). The second intermediate hosts of M. yokogawai include the sweetfish (Plecoglossus altivelis), dace (Triolodon sp.) and perch (Lateolabrax japonicus). The fish hosts for M. takahashii are the carp (Cyprinus carpio), and dace (Tribolodon taczanowskii); those for M. miyatai are found under the scale of the sweetfish, dace, pale chub, dark chub, and common fat-minnow. Dogs, rats and cats are reported to be naturally infected final host.

Life cycle. The three common parasites of man, S. haematobium, S. japonicum and S. mansoni have similar life cycles. Eggs are passed out from the urine (S. haematobium) or from the feces (S. japonicum and S. mansoni); they hatch in aggregations of water such as ponds, lake edges, streams and canals. From the eggs, miracidia hatch into the water where they penetrate into the suitable snails. In the snails, they develop two generations of sporocysts; the second of which produces fork-tailed cercariae. These penetrate the skin when a new host comes into contact with contaminated water. Once get into the skin, the cercariae shed their tails to become schistosomulae, which migrate through the tissues until they reach the portal venous system of the liver. The males and females copulate before settling down in pairs in the venous system of the liver. S. haematobium usually migrates to the venous plexus of the bladder; other species (including the geographically localized S. intercalatum and S. mekongi), to the rectum where spiny eggs are laid. The eggs penetrate into the bladder or rectum.

Life cycle. Trophozoites do active functions in favorable environments and become cysts in less favorable environment for survival. Acanthamoeba has wide distribution in soil, fresh water, sea water, etc. Some species show facultative parasitism in mammals and in several vertebrates, fish and presumably other animals.


One Clonorchis sinensis and 3 Echinostoma hortense recovered from a patient after treatment.

Sung-Tae Hong

Morphology. The adults are elongated, thread-like worms, measuring 35 to 40 x 0.1 ㎜(male) and 90 to 100 x 0.25 ㎜ (female). The microfilariae show nuclei in their body after staining and various internal structures can also be seen. A thin and delicate sheath surrounds the organism. The anterior end is blunt and round. The posterior end culminates into a point that is free of nuclei.

Morphology. The adult worms of B. malayi resemble those of W. bancrofti measuring 50㎜ (female) and 25㎜ (male) in length. The typical B. malayi microfilaria possesses a sheath, a round anterior end, and numerous nuclei. The characteristic that distinguishes it from the other sheathed organisms is the presence of two distinct nuclei on the tip of the pointed tail.

Morphology. Trophozoite is measured 15 to 50 ㎛ in diameter and has a large karyosome, frequently with irregular shape and eccentric in nucleus. Cysts overlap the size range of E. histolytica, being 10 to 35 ㎛ in diameter. One to eight nuclei including the eccentric location of the karyosome are observed.

Morphology. Trophozoite is smaller than E. histolytica, ranged 5 to 12 ㎛ in diameter, and has a large karyosome, frequently irregular nucleus. Cysts overlap the size range of E. hartmanni, being 8 to 9 ㎛ in diameter. One to four nuclei including the large karyosome are observed.

Morphology. Adult worms are very slender, measuring 3.8-4.8 mm (male) and 4.9-6.7 mm (female) in length. The eggs differ from hookworm in their size (75-91 x 47 ㎛), having more pointed ends with advanced morula stages.

Morphology. Adult worms are flat, slender leaf-shaped between 10 and 25 mm in length, and two branched testes are located in posterior one third. The yellow to light brown eggs measure about 30 by 15 ㎛. The operculum has prominent shoulder rim, and on the opposite side, comma shaped terminal knob locates.

Morphology. Adult worms are large leaf-like, 20 to 30 mm in length. At the anterior end, distinct conical projection is observed. The ceca and testes are highly branched. The tegument contains spines. The eggs measure about 140 by 80 ㎛.

Morphology. Adult worm is only 10-45 mm long and 0.5-1 mm wide, with 100-200 segments. The eggs (30-50 ㎛) are oval to spherical and almost colorless.


Microfilaria of Mansonella species.

Tai Soon Yong

Morphology. Ring: delicate cytoplasm; 1 to 2 small chromatin dots. Trophozoite: seldom seen in peripheral blood; compact cytoplasm. Schizont: seldom seen in peripheral blood; mature = 8 to 24 small merozoites. Gametocyte: crescent or sausage shape.

Morphology. Ring: sturdy cytoplasm; large chromatin, Trophozoite: compact cytoplasm; large chromatin; occasional band forms. Schizont: mature = 6 to 12 merozoites. Gametocyte: round to oval; compact; may almost fill RBC.

Morphology. Ring: sturdy cytoplasm; large chromatin. Trophozoite: compact with large chromatin. Schizont: mature = 6 to 14. Gametocyte: round to oval; compact; may almost fill RBC.

Morphology. Ring: large cytoplasm; large chromatin dot. Trophozoite: large ameboid cytoplasm. Schizont: large, may almost fill RBC; mature = 12 to 24 merozoites. Gametocyte: round to oval; compact; may almost fill RBC.

Morphology. Female worms range from 20 to 35 cm in length, while males are seldom more than 30 cm long. The female worms may be as thick as a lead pencil; the males are definitely more slender and may be distinguished by an incurved tail. Both sexes are creamy white, sometimes with a pinkish cast, and the cuticle has fine circular striations.

Morphology. Living adult worms are pinkish-brown in color and bean-shaped (7 to 15 mm in length, 3 to 8 mm in width, and 3 to 5 mm in thickness). It contains characteristic ovary in the middle part of the worm. The golden brown colored large immature eggs are approximately 45-60 x 80-100 µm. They contain operculum at one side and abopercular thickening at other side. The metacercariae in the 2nd intermediate host are spherical in shape measuring 220-450 µm.

Morphology. The adult worm reaches up to 10 m with 3,000 proglottids. The scolex is elongated and spoon shaped with two long sucking grooves. It measures 1 mm in width by 2.5 mm in length. The mature and gravid proglottids are broader than long, with the typical rosette-shaped uterus. They measure up to 2 cm in width. The eggs are oval and operculated. They measure 65~70 by 45~50 ㎛.

Morphology. Threadlike adult worms measure 5 cm in males, and 50 cm in females.

Morphology. T. vaginalis is a colorless pyriform flagellate, 13x17 ㎛ in fresh preparations. There are four anterior flagella and an undulating membrane, and a recurrent flagellum which is closely associated with the undulating membrane. A costa arises in the kinetosome complex and a parabasal body lies near the nucleus. The axostyle extends from the area of the kinetosome. There are many hydrogenosomes along axostyle and costa.

Morphology. The pear-shaped trophozoites measure 6-24 ㎛ in length by 3-10 ㎛ in width. Three flagella are extended from the anterior end. A spiral groove crosses over the middle half of the body. A slit-like cytosome, enclosing a fourth flagellum, is located in the anterior portion of the body. A nucleus with central karyosome is located near the front end. The lemon-shaped cysts measure 6-10 ㎛ in diameter. The cyst wall is relatively thick. It has hyaline protrusion. The single nucleus and the cytostome remain in the cysts.

Morphology. Adult worms measure 10-70 cm in length, and 2-3 mm in width. The scolex has four suckers with 40-60 hooklets arranged in 3-5 rows around the rostellum. Immature proglottids are trapezoidal, become progressively long with rounded sides toward the posterior end. Mature proglottids contain two sets of reproductive organs with a genital pore on each lateral margin. In the gravid proglottid, eggs are enclosed by thin sacs to form egg-capsules or egg-ball. The eggs are spherical, measuring 40-50 ㎛ in diameter. The oncosphere is covered by a thin eggshell and an embryophore.

Morphology. The adult is thin and long. The female is about 15 mm long with thin both ends. The male is about 10 mm long, with a curled tail. In female, the vagina opens at the vulva located little behind the center of the esophagus on the ventral side.

Both the adult and the larva are similar to those of T. callipaeda, but the position of the vulva in the female differs. The mode of alignment of papillae behind the cloaca in the male is different also. The intermediate hosts are insect: Fannina canicularis and F. benjamini.

Morphology. The majority of trophozoites measure from 15 to 30 ㎛. The hyaline ectoplasm, sharply separated from the endoplasm, constitutes about one-third of the entire trophozoite. The thin, fingerlike ectoplasmic pseudopodia are extended rapidly. Hematoxylin staining reveals a nuclear membrane, the inner surface of which is lined with uniform chromatin. The small, deeply staining karyosome is centrally located. The round or oval cysts measure 10 to 20 ㎛ in diameter, and contain one to four nuclei and sausage-shaped chromatoid bodies.

Morphology. T. gambiense exists in human as a trypomastigote form. It is elongated spindle-shaped organism with blunt posterior end, and with finely pointed anterior end.

Morphology. T. rhodesiense exists in human as a trypomastigote form. It is morphologically indistinguishable from T. gambiense.

Morphology. Round to oval oocyst has 4-6 ㎛ in diameter. Oocyst seems often refractile at wet smear. Black dot or small vacuoles in oocyst could be seen after modified acid fast staining. Sporozoite and merozoites have apical complex (microneme, rhoptry, conoid, preconoidal ring) at the anterior most part.

Morphology. The trophic forms are ameboid of 2-3 ㎛ diameter. It has one nucleus and one tubular mitochondrion. Cystic forms have cyst wall of polysaccharides and globular shape of 6-8 ㎛ diameter. One cystic form includes 8 intracystic bodies which are sickle-shaped after maturation.

Morphology. The trypomastigote form is found in the circulating blood. This form is slender, about 20 ㎛ in length, and its posterior end is pointed. The body of stained specimens is U- or C-shaped. The nucleus is located near the middle of the body, and the kinetoplast is located near the posterior end. The undulating membrane is weakly developed, with two or three convolutions. The free flagellum extends to anterior portion. Intracellular amastigotes are oval-shaped and measure 1.5-4 ㎛ in diameter.

Morphology. The female worm measures 8 to 13 mm long and has a pointed tail (hence the common name "pinworm"). The male worm is inconspicuous, about 2~5 mm long. The eggs are oval, compressed laterally, and flattened on one side and measure 50 to 60 ㎛ long by 20 to 30 ㎛ wide.

Morphology. The adults are cylindrical with a head bent sharply backwards giving them a hooked appearance. The average adult hookworm usually measure about 5-10 ㎜ in length by 0.2 to 0.5 ㎜ in width. The hookworm species are mainly differentiated by their buccal capsule and the arrangement of rays in the bursa. The hookworm eggs measure 60-75 ㎛ by 35-40 ㎛. Eggs may be unsegmented or show visible embryonic cleavages, usually two, four or eight cell stages. However, eggs in stool samples that have been kept at room temperature over time may reveal a developing larva.

Morphology. The adult worms are 10.8-12.6 mm in length and 2.6-3.2 mm in width. Head crown with 37-38 collar spines and abnormal location or disappearance of one or two testes are characteristic. The eggs are oval-shaped and measure 99-116 x 65-76 ㎛.

Morphology. The adult tapeworms are minute, measuring 3 to 6 mm in length. The size of eggs are about 35 ㎛ in diameter. The oncosphere metamorphoses into a unilocular hydatid cyst containing protoscolices oe free hydatid sands in the intermediate hosts.

Morphology. The adult worms are similar to E. granulosus with smaller body lengths of 1.2 ㎜ ~ 3.7 ㎜. Cyst has a thin outer wall that grows and infiltrates into the surrounding host tissues. Fluid-filled pockets containing protoscolices may be produced. The cysts break off and metastasize to other parts of the body, forming alveolar or multilocular hydatid cysts in humans.

Morphology. Adult worms are 6-10 mm long and 1.5-2.5 mm wide. The oral sucker is smaller than the ventral one. The testes are slightly lobed and lie almost tandem, immediately posterior to the ventral sucker, with the ovary directly behind them. The brown eggs measure 36-45 ㎛ by 20-30 ㎛ and are operculated and embryonated when laid.

Morphology. Adult O. viverrini is 7-12 mm long and 1.5-3 mm wide, transparent, and elongate. The ratio of length to width is approximately 2:1. A pair of testes is located posteriorly. The uterus is a coiled tubule and transverse follicles lie laterally. The eggs are yellowish-brown, oval, and have a tubercle-like knob at the opercular end. The eggs average 28 ㎛ by 16 ㎛ in size and contain a miracidium when laid.

Morphology. Adult worms measure 7-12 mm long and 1.5-3 mm wide.


hyun Park

Morphology. The parasite (10∼18 x 5∼9 mm in size) is broad, flat, and oval to fusiform. The suckers are large, the oral sucker is larger than the ventral sucker. The eggs (50∼80 x 35∼40 ㎛) are embryonated in the uterus.

Morphology. The lice are 1.5-2.0 mm in length and nearly as broad as long. The adult has a crab-shaped body, a rectangular head, and three pairs of legs. The front pair of leg is much more slender and has smaller claws than the other two pairs. The characteristic large claws are located on the middle and hind-legs.

Morphology. The amastigotes are small elliptical, intracellular organisms of 2-3 ㎛. It has one nucleus and one kinetoplast but not free flagellum. The promastigote has one anterior free flagellum. The bodies are 6-10 ㎛ long and 1 ㎛ wide.

Morphology. The adult worms are minute and slender; the females are no more than 2.2 mm long by 90 ㎛ wide, and the males are 1.2 mm long by 60 ㎛ wide. The anterior part is filled with the stichocytes. The larvae encapsulated within the muscle fibers are 0.8 to 1.0 mm long, and they also have stichocytes in the anterior part of body.

Morphology. Most of the worms in humans are advanced third-stage larvae or very young adult worms. Their general morphology is similar to that of adult, with subglobular head bulb containing more than 4 rows of hooklets (G. nipponicum: 3 rows). Gnathostome larvae are identified on the basis fo several characteristics: the shape of body, the number of rows of hooklets at the head bulb, the number of hooklets in each row, and the characters with the extension of spines covering the body.

Morphology. All species of house dust mites are very similar in morphology, sized 370-430 ㎛ in female and 300-350 ㎛ in male. Their body color is milky white. The fourth legs are significantly smaller than the others. The tegument is covered with fine wrinkles. Morphological differences between Df and Dp are the shape of bursa copulatrix in female, being a cup-shape in Df and flower-shape in Dp. In male, a pair of the first legs are extraordinarilly larger in Df, whereas not larger than the other three pairs in Dp. In case of larvae and nymphs, the wrinkles of d2-d3 are horizontal in Df whereas vertical in Dp.

Morphology. The larvae of the family Anisakidae are characterized by the presence of three bilobed lips, a boring tooth near the dorsal lip, large excretory gland cells in their anterior region, and a ventriculus between the esophagus and the intestine. Distinction among the three genera depends on the presence or absence of an intestinal cecum and a ventricular appendix.

Morphology. The adult worms are elongate, 2.7-2.8 by 0.5-0.6 mm in body size. Ventral sucker is median, large, muscular, posterior to intestinal bifurcation, and 0.16-0.20 mm in diameter. Genital sucker is prominent and armed with 92-115 spines in a single row. Two testes are a little obliquely tandem and globular in shape near posterior one-third of body. Intrauterine eggs are small but broadly oval in shape with relatively thick shells, 24-28 by 16-19 mm in size.

Morphology. The adult worm is small, pyriform or ovoid in shape and 0.4-0.7 by 0.3-0.4 mm in size. It is characterized by the position of ventral sucker, which is slightly deviated to the right side of the body, and the presence of an elongated sac-like seminal vesicle on the opposite side of the ventral sucker. Intrauterine egg is yellowish in color, oval, and a little elongated in shape with slightly attenuated anterior end, and 25-29 by 11-13 mm in size.

Morphology. The adult worm is dorso-ventrally flat, tapering anteriorly, globular and bluntly ending posteriorly, and 0.5-0.8 by 0.3-0.4 mm in size. Neighboring the ventral sucker, genital apparatus present left anterolaterally, 0.06-0.10 by 0.03-0.05 mm in size. Genital apparatus are crescent shape and present two groups of small spine like gonotyls. Intrauterine egg is yellowish brown color, ovoid, operculated, thick shelled, very similar to those of C. sinensis, and 20-23 by 11-13 mm in size.

Morphology. The adult worm is small, flattened pear- or club-shaped, spinose and 0.9-1.0 by 0.3-0.4 mm in size. Vesicular seminalis constricted into 2 to 4 portions. Acatebulum is embedded in parenchyma and modified into non-suctorial organ with numerous spines projecting into genital atrium. Intrauterine egg is dark brown color, ovoid, operculated, thick shelled, very similar to those of C. sinensis with 34-38 by 20-23 mm in size.

Morphology. The adult parasite is very small (the smallest of all human intestinal trematodes reported in the Republic of Korea), 0.4-0.5 by 0.2-0.3 mm in size. This is characterized by a large oral sucker, a small ventral sucker, short caeca, two compact masses of vitellaria, and a unique ventral pit.

Morphology. The adult worms are conspicuously bisegmented, spoon shaped, 0.8-1.2 by 0.4-0.5 mm in size, and well developed ventral concavity of the forebody. Tribocytic organ is approximately circular or elliptic, about 1/3 length of the forebody, and lying just behind the posterior border of the ventral sucker. The eggs are golden yellow in color, elliptical with thin shell, asymmetrical, operculum inapparent, no wrinkles, and 86-99 by 55-63 mm in size.

Morphology. The adult worms measure 0.5-1.0 mm long and wide up to 0.3 mm. The body is elongated, foliate, with lateral edges of the forebody curved ventrally. The head collar is prominent, with a row of 12 spines on each side; ventral spines in two alternating rows, dorsal spines in a single row. The cuticle is spineous. The testes are directly tandem, and cirrus sac is ellipsoidal, and is situated just behind the bifurcation of the intestine. The ovary is ovoid or elliptical and situated on posterodextral to acetabulum. The vitellaria extend from the preacetabular level to the posterior extremity. The uterus is short. The eggs are broad, oval with thin shell, tiny operculum, inapparent abopercular wrinkle, and 76-87 by 52-63 mm in size.

Morphology. The flukes of the Genus Metagonimus are characterized by their small body, 1.0-2.0 mm long by 0.4-0.6 mm wide, laterally located ventral sucker, absence of genital sucker or ventrogenital apparatus, and egg size. Metagonimus takahashii differs from M. yokogawai in the position of two testes (anterior testis separated from the posterior testis), the distribution of vitelline follicles (more abundant and crossing over the posterior-most end), and by larger size of eggs (M. yokogawai, 28-30 mm; M. takahashii, 32-36 mm). Metagonimus miyatai morphologically differs from M. yokogawai and M. takahashii in the position of the posterior testis (separated greatly from the anterior one), the distribution of vitelline follicles (never crossing over the posterior testis), and the intermediate size of eggs (28-32 mm).

Morphology. Schistosomes are dioecious and measure 10 to 20 mm in length and 0.5-1.0 mm in width. The male has a deep ventral groove known as the gynaecophoric canal, in which the female lies during copulation. Both sexes have 2 suckers, an anterior and a ventral sucker. The gut of the female worm appears dark because it is filled with deposits of haematin (breakdown product of haemoglobin). The life span may extend to 30 years but the mean longevity is about 5 years.

Morphology. Acanthamoeba trophozoites (25-40 ㎛) are quite large compared to other protozoa. The most typical trait is the needle-like projections called acanthopodia for movement. Cytoplasm contain numerous mitochondria, vesicles, phagocytic and pinocytic vacuoles, ribosomes and other organells. The cyst diameter varies a great deal (15 to 28 ㎛) and the cyst wall appears as a two-layer membrane: the outer wall (exocyst) is moderately undulated, while the endocyst shows a typically polygonal arrangement.


Experimental subcutaneous leishmaniasis on feet of a mouse, infected with Leishmania major.

Sung-Tae Hong


Skin ulceration on the back of a mouse, experimentally infected with Leishmania major.

Sung-Tae Hong


A gerbil with skin lesion on the nose after inoculation of Leishmania major.

Sung-Tae Hong

Pathology and Clinical Symptoms. Most of the adult patients experience no symptoms. Sometimes lymphangitis is severe and is accompanied by high fever and headache. In addition to lymphatic involvement, some patients may show epididymitis and orchitis. In the intervening period, repeated attacks of acute lymphangitis may continue. The classical symptoms of this stage are elephantiasis, hydrocele and chyluria.

Pathology and Clinical Symptoms. The pathology and clinical symptoms of B. malayi infection mimic those of W. bancrofti infection.

Pathology and clinical symptoms. Non-pathogenic.

Pathology and clinical symptoms. Non-pathogenic amoeba.

Pathology and clinical symptoms. The worms ingest blood and produce toxin in the mucosa of small intestine. Symptoms are usually mild, but in heavy infection; abdominal pain, malaise and other symptoms can be seen.

Pathology and clinical symptoms. The mechanical irritation and toxic metabolites of the parasite cause inflammatory responses in biliary epithelium. Obstruction of biliary tract, pyogenic cholangitis, pancreatitis, cholecystitis, cholelithiasis, liver cirrhosis, and cholangiocarcinoma may be induced as the result of heavy and chronic infection.

Pathology and clinical symptoms. The triad of fever, hepatomegaly, and eosinophilia in endemic area suggests fascioliasis. Symptoms and signs are associated with biliary obstruction and cholangitis. Acute epigastric pain, pruritus, and jaundice are common. Worms in human infections may be frequently found in ectopic foci.

Pathology and clinical symptoms. Light infections are asymtomatic. When large numbers of worms are present, they may give rise to abdominal pain, diarrhea, headache, anorexia and various non-specific symptoms.

Pathogenesis and clinical symptoms. The disease is caused by the direct effects of red cell invasion and destruction by the asexual parasite and the host's reaction. The symptoms of uncomplicated malaria can be rather non-specific. The most frequent symptoms include fever and chills, which can be accompanied by headache, myalgias, arthralgias, weakness, vomiting, and diarrhea. Other clinical features include splenomegaly, anemia, and thrombocytopenia. In P. falciparum infections, membrane protuberances appear on the erythrocyte's surface, which make the erythrocytes stick inside the small blood vessels and uninfected red cells. These processes cause obstructions of capillaries and venules. Thus infections caused by P. falciparum can progress to severe, potentially fatal forms with CNS involvement (cerebral malaria), acute renal failure, severe anemia, or adult respiratory distress syndrome.

Pathogenesis and clinical symptoms. The disease is caused by the direct effects of red cell invasion and destruction by the asexual parasite and the host's reaction. The symptoms of uncomplicated malaria can be rather non-specific. The most frequent symptoms include fever and chills, which can be accompanied by headache, myalgias, arthralgias, weakness, vomiting, and diarrhea. Other clinical features include splenomegaly, anemia, thrombocytopenia.

Pathogenesis and clinical symptoms. The disease is caused by the direct effects of red cell invasion and destruction by the asexual parasite and the host's reaction. The symptoms of uncomplicated malaria can be rather non-specific. The most frequent symptoms include fever and chills, which can be accompanied by headache, myalgias, arthralgias, weakness, vomiting, and diarrhea. Other clinical features include splenomegaly, anemia, and thrombocytopenia.

Pathogenesis and clinical symptoms. The disease is caused by the direct effects of red cell invasion and destruction by the asexual parasite and the host's reaction. The symptoms of uncomplicated malaria can be rather non-specific. The most frequent symptoms include fever and chills, which can be accompanied by headache, myalgias, arthralgias, weakness, vomiting, and diarrhea. Other clinical features include splenomegaly, anemia, and thrombocytopenia.

Pathology and clinical symptoms. The ingestion of small numbers of infective eggs at any one time probably gives rise to no recognizable symptoms, but larger numbers may provoke pneumonitis during larval migration through the lung. This may occur from 4 days to 2 weeks after infection. During this period sensitive persons may develop asthma attacks, which can continue until the eventual elimination of the adult worms. A few adult worms in the bowel are unlikely to cause symptoms unless they migrate through the ampulla of Vater into the pancreas, bile ducts, gallbladder, or liver, or up the esophagus. A heavy infection is likely to cause bowel obstruction, especially in children. In one series, three fourths of children with bowel obstruction presented with fever and generalized malaise.

Pathology and clinical symptoms. Usually no symptoms are observed when the parasites migrate in the peritoneal cavity. In rare cases of heavy infection, non-specific symptoms (such as easy fatiguability, myalgia, and mild fever) can be manifested. When parasites invade the lung, several symptoms including pleuritic and chest pain, cough, and rusty sputum may be present. Remarkable laboratory findings are peripheral eosinophilia, leukocytosis, and elevated serum levels of total IgE. Hydropneumothorax, parenchymal infiltration, and pleural effusion are the main pathologic changes. As time passes, worms are surrounded by thick fibrous granuloma. Generalized or localized fibrosis of the lungs and cystic dilatation of bronchi are the main histopathologic changes. The patients continue to complain about several symptoms. If not treated, the symptoms can last several years. Ectopic paragonimiasis results in granulomatous lesions in the organs other than the lung. The most commonly affected organs include liver, spleen, omentum, and ovary. Migrating subcutaneous lesions can also be developed. The most serious illness is cerebral paragonimiasis, which is associated with several neurological symptoms. Migrating worms frequently invoke subacute hematoma. Chronic cerebral paragonimiasis, which results from calcifying granuloma, is mainly manifested by partial seizure, headache, and homonymous hemianopia. Predilection sites of the cerebral involvement include temporal, occipital, and parietal lobes.

Pathology and clinical symptoms. Symptoms depend on the mass of the worm, amount of its by-products absorbed by the host, and the host's susceptibility to the foreign substances. Some infected people show no symptoms. There may be intestinal obstruction, diarrhea, abdominal pain, or anemia.

Pathology and clinical symptoms. The adult worms induce fibroblastic reaction in the host which causes the worms to become enveloped in fibrous scars: onchocercal nodule or onchocercoma of firm, round, nontender, and varying in diameter of 0.5 to 10 cm or more. These nodules tend to occur on anatomic sites where the bone is superficial, such as the scalp, scapulae, elbows, iliac crests, and knees. Heavy and long term infection, in endemic area, can make a irreversible eye changes. Symptomatology of ocular onchocerciasis begins with photophobia and progresses through gradual blurring of vision to blindness.

Pathology and clinical symptoms. T. vaginalis causes itching, intense inflammation, and white discharge (leukorrhea) in women. Less symptomatic in chronic stage. Nonspecific irritating urethritis or prostatitis are caused in men, but usually asymptomatic.

Pathology and clinical symptoms. Usually considered to be nonpathogenic but may cause intestinal disorders like diarrhea in heavy infected cases.

Pathology and clinical symptoms. Most infected persons are asymptomatic. Severe infection may cause indigestion, abdominal pain, diarrhea, anal pruritus, and nervous symptoms.

Pathology and clinical symptoms. In case of human infection, it is generally noticed by severe foreign body sensation in early stage. In dogs and cats, however, chronic conjucntivitis induces photophobia, corneal opacity, or ulcer of the cornea.

Pathology and clinical symptoms. The lesions produced by E. histolytica are primarily intestinal, and secondarily extraintestinal. The intestinal lesions are confined to the large intestine, frequently cecal and sigmoidorectal regions. The typical flask-like primary ulcers to large necrotic areas are produced. In acute amebiasis, there is severe dysentery with numerous small stools containing blood, mucus and necrotic mucosa accompanied by acute abdominal pain, tenderness and fever. Chronic amebiasis is characterized by recurrent attacks of dysentery with gastrointestinal disturbance. In extraintestinal amebiasis, the liver is invaded chiefly, resulting amebic hepatitis or liver abscess. It is characterized by an enlarged, tender liver, with pain in the upper right hypochondrium. Less frequently, lung abscess, splenic abscess, brain abscess or cutaneous amebic lesions are seen.

Pathology and clinical symptoms. The disease varies in severity from a mild type to a severe fulminating type resembling that of T. rhodesiense. There may be a local inflammatory sign on the biting site. The acute disease lasts a year and is characterized by irregular fever, headache, joint and muscle pains, and a rash. The lymph nodes including postcervical group are enlarged (Winterbottom's sign). Gradually the chronic phase of the disease ensues, with the development of characteristic central nervous system changes. Diffuse meningoencephalitis and meningomyelitis develop. Evidence of nervous impairment becomes prominent, and develops a terminal sleeping stage. Death ensues either from the disease or from intercurrent infections.

Pathology and clinical symptoms. Rhodesian trypanosomiasis runs a more rapid and fatal course than the Gambian disease does, often terminating within a year. The pathologic changes are similar to those of Gambian sleeping sickness, but the febrile paroxysms are more frequent and severe. Edema, myocarditis and emaciation are more prominent. Chronic lesions in the central nervous system are less frequently encountered since death intervene before marked cerebrospinal changes occur.

Pathology and clinical symptoms. Watery diarrhea is the most frequent symptom, and can be accompanied by dehydration, weight loss, abdominal pain, fever, nausea and vomiting. In immunocompetent persons, symptoms are limited within 1 to 2 weeks; they can be chronic and more severe in immunocompromised patients, especially those with CD4 counts < 200/ul. Microvilli of the small intestine disappear and loss of the ability to produce digestive enzymes and decrease of digestion area can cause indigestion and malabsorption.

Pathology and clinical symptoms. The main pathological finding is exfoliation of pneumocytes and cell infiltration in the interstitial tissue. The mass of organisms, necrotic cell debris, and exudate fills the air space of the alveolar cavity, and thus respiration failure is induced. Major symptoms are fever, non-productive cough and respiration difficulty.

Pathology and clinical symptoms.
1) Acute stage: Acute symptoms occur mostly in children but rarely, lasting 4 to 8 weeks before disappearing even without treatment. Symptoms may include fever, fatigue, enlarged liver or spleen and swollen lymph glands. In some cases, eye swelling (Romana`s sign) may occur usually where a bite was received or where feces were rubbed into the eye. Infants in the acute stage of Chagas disease may experience brain swelling, which can lead to death.
2) Chronic stage: Chronic symptoms develop after a long symptom-free (or silent) period (10-20 years). Irreversible damage to the internal organs-the heart, esophagus, colon and to the peripheral nervous system-can occur. For individuals with compromised immune systems (such as those living with HIV/AIDS), the effects of Chagas disease can be severe.

Pathology and clinical symtoms. Many cases of E. vermicularis infection are asymptomatic. The most striking symptom of this infection is pruritus, which is caused by the migration of the female worms from the anus onto the perianal skin.

Pathology and clinical symptoms. Sometimes some itchy papules at the site of larval penetration, ground itch, occurs. Patients with chronic infections may experience vague mild GI symptoms, slight anemia due to loss of blood and weight loss or weakness. In heavy infections, microcytic hypochromic anemia is produced.

Pathology and clinical symptoms. Gastrointestinal symptoms like nausea, vomiting, abdominal pain, and diarrhea can be observed.

Pathology and clinical symptoms. The larval tapeworm of E. granulosus causes unilocular hydatid disease in humans. Brood capsules sprout from the germinal layer and finally transformed into a vesicle containing scolices and free 'hydatid sands'. The liver is the most commonly involved organ. The chief clinical manifestations are pressure symptoms and anaphylactic symptoms with localized or generalized secondary hydatidosis.

Pathology and clinical sysptoms. The cyst grows very slowly and metastases occur by direct extension or via the blood or lymphatic system. The liver is most frequently involved organ in humans. Hepatomegaly, reduced liver function, obstrucion of bile duct and portal vein, and ascites can be seen.

Pathology and clinical symptoms. The flukes penetrate into the fine branches of the bile ducts, in which they lie greatly extended and attached by means of their suckers. The clinical picture in severe cases consists of anemia, edema and emaciation, but many cases show no clinical signs.

Pathology and clinical symptoms. The pathologic changes induced by the worms are apparently the result of mechanical irritation caused by the worm suckers, toxic metabolic substances, immunologic response of the hosts, and secondary bacterial infection. Severe opisthorchiasis has been associated with cirrhosis, obstructive jaundice, pancreatitis, cholangitis, and cholangiocarcinoma.

Pathology and clinical symptoms. Eurytremiasis usually causes mild symptoms. Heavy infections, however, may be marked by gastrointestinal disturbances, including abdominal distress, flatulence, vomiting, diarrhea or constipation. Jandice, an enlarged liver, and systemic symptoms are reported. Eosinophilia is rare.

Pathology and clinical symptoms. There may be either no symptoms, or there may be itch due to allergic reactions to the injected saliva. The skin may become thickened and shows spots of hyperpigmentation in the chronic case.

Pathology and clinical symptoms. The mainly involved organs are liver, spleen, and bone marrow. Most of the cells of the organs are destroyed and replaced by granulation tissues. Characteristic symptoms are splenomegaly, hepatomegaly, anemia, and fever. General weakness, emaciation, secondary infection, and pancytopenia are also frequent.

Pathology and clinical symptoms. The mainly involved organ is the skin in human. A subcutaneous nodule with central necrosis is the main pathologic symptom.

Pathology and clinical symptoms. The pathologic changes and the symptomatology are divided into three successive stages, i.e., intestinal, muscle invasion and convalescence. In the intestinal stage, inflammation of the duodenal and jejunal mucosa caused by the penetration and development of the adult worms may produce symptoms of malaise, nausea, diarrhea and abdominal pain. In the stage of muscle invasion, typical manifestations are fever, facial edema, pain, swelling, weakness of involved muscles, and peripheral eosinophilia. In the convalescence stage, fever generally subsides and muscle symptoms begin to decrease.

Pathology and clinical symptoms. The pathologic manifestations of gnathostomiasis consist of inflammation, edema, and tissue destructions along with the path of larvae. Much of the tissue reaction is believed to be allergic, but the number and size of larvae, and their invading sites are important factors also. The main organs affected are as follow: subcutaneous tissues, skin, central nerve system, eye, lungs and gastrointestinal tract.

Pathology and Clinical Symptoms. The gastric or intestinal wall is thickened as a result of edema and inflammation. Ulcers or hemorrhages are occasionally seen. The mechanism of pathologic changes may be associated with allergic reactions to the secretory-excretory products of the larvae. Main symptoms are epigastric pain, nausea and vomiting which develop 6 hours after the ingestion of raw seafoods. P. decipiens larvae often provoke a tingling throat syndrome, associated with larval migration from the stomach to the mouth.

Pathology and clinical symptoms. Refer to Metagonimus Species.

Pathology and clinical symptoms. Refer to Metagonimus Species.

Pathology and clinical symptoms. Refer to Metagonimus Species.

Pathology and clinical symptoms. Refer to Metagonimus Species.

Pathology and clinical symptoms. Infected people complain of abdominal discomfort and indigestion. General symptoms such as fever, anorexia, weight loss, easy fatiguability, and weakness may be accompanied.

Pathology and clinical symptoms. Comparing it with other intestinal flukes such as heterophyids and echinostomes that cause only mild gastrointestinal troubled unless severely infected, N. seoulense seems to be more harmful for their definitive hosts. The human case complained of severe symptoms, including headache, epigastric cramps, fullness, discomfort, pain, and sudden onset of fever.

Pathology and clinical symptoms. Most of the recorded human cases were lightly and chronically infected. In such cases no significant symptoms were found. However, heavily infected cases suffered from digestive symptoms or signs, such as abdominal discomfort, diarrhea and anorexia.

Pathology and clinical symptoms. Except for heavy infections, there is neither significant injury of the intestine nor marked symptoms. In heavy infections, irritation of the intestinal mucosa may result in a chronic intermittent mucous diarrhea with colicky pains, abdominal discomfort and tenderness. There is eosinophilia, but no anemia. When he worms penetrate the intestinal wall, the eggs may get into the lymphatics and venules and causes granulomatous lesions in such distant foci as the heart and brain.

Pathology and clinical symptoms. The adults do not multiply and the eggs are the main cause of pathology in schistosomiasis. The eggs penetrate the blood vessels and the host tissues by secreting proteolytic enzymes through ultramicroscopic pores in their shell. However, many eggs become stranded in the tissues or are carried via the blood stream to other organs of the body. The host reaction to the eggs may vary from small granulomas to extensive fibrosis. The extent of damage is generally related to the number of eggs present in the tissues. Complete immunity does not occur with initial infection, and repeated infection is common in endemic areas.
Many infections are asymptomatic. Acute schistosomiasis (Katayama's fever) may occur weeks after the initial infection, especially by S. mansoni and S. japonicum. Manifestations include fever, cough, abdominal pain, diarrhea, hepatospenomegaly, and eosinophilia. Occasionally central nervous system lesions occur. Continued infection may cause granulomatous reactions and fibrosis in the affected organs, which may result in manifestations that include: colonic polyposis with bloody diarrhea (Schistosoma mansoni mostly); portal hypertension with hematemesis and splenomegaly (S. mansoni, and S. japonicum); cystitis and urethritis (S. haematobium) with hematuria, which can progress to bladder cancer; pulmonary hypertension (S. mansoni, S. japonicum, more rarely in S. haematobium); glomerulonephritis; and central nervous system lesions.

Pathology and clinical symptoms. Most of GAE patients are immuno-compromised individuals. The infection is insidious in onset and with a prolonged clinical course. Altered mental status, headache, and stiff neck are prominent symptoms. In the case of keratitis, the infection remains confined to the cornea. It is suspected in patients who have corneal ulcer which do not respond to the usual medications and in patients who are contact lens wearer.

Diagnosis. The examination of fresh Giemsa-stained blood for W. bancrofti microfilariae serves as the laboratory diagnostic method of choice. Samples should be collected during night time, because this organism exhibits nocturnal periodicity. Serologic methods are also available commercially.

Diagnosis. See W. bancrofti.

Diagnosis. Detection of cysts in the stool.

Diagnosis. Detection of cysts in the stool.

Diagnosis. Detection of eggs in fresh stool samples. Fecal culture methods can also be used.

Diagnosis. Detection of eggs in feces makes definite diagnosis. ELISA and radiologic techniques (mainly sonography) can provide indirect evidences of clonorchiasis.

Diagnosis. Detection of eggs in feces. Enzyme-linked immunosorbent assay (ELISA) are also used for diagnosis of ectopic fascioliasis. Radiologic techniques can provide indirect evidences of fascioliasis.

Diagnosis. Detection of eggs in feces.

Diagnosis. Microscopic identification is the method most frequently used to demonstrate an active infection. Molecular diagnostic techniques can complement microscopy. Antibody test can detect past (not necessarily active) infections.

Diagnosis. Microscopic identification is the method most frequently used to demonstrate an active infection. Molecular diagnosis techniques can complement microscopy. Antibody Detection can detect past (not necessarily active) infections.

Diagnosis. Microscopic identification is the method most frequently used to demonstrate an active infection. Molecular diagnostic techniques can complement microscopy. Antibody test can detect past (not necessarily active) infections.

Diagnosis. Microscopic identification is the method most frequently used to demonstrate an active infection. Molecular diagnostic techniques can complement microscopy. Antibody test can detect past (not necessarily active) infections.

Diagnosis. Detection of eggs. A diagnosis may be made by finding larvae in the sputum or, more readily, in gastric washing.

Diagnosis. Detection of eggs in feces is the diagnostic choice. Intradermal test is also available in large-scale based screening but not good for individual patient due to its low specificity. Enzyme-linked immunosorbent assay (ELISA) and immunoblot are reliable in detecting specific IgG antibodies. In case of cerebral paragonimiasis, CSF tests are highly recommended. Radiologic examination by high resolution chest CT provide definitive clue for paragonimiasis. Brain CT/MRI are also highly diagnostic either in active or in chronic calcified neuroparagonimiasis.

Diagnosis. Diagnosis is based on the recovery of the characteristic eggs or proglottids. Proglottids are often passed in chains in a few cm or longer. The proglottid morphology with the rosette-shaped uterus confirms the species.

Diagnosis. Definitive diagnosis depends on finding adult worms in excised nodules, or microfilariae in affected skin.

Diagnosis. Diagnosis depends on observing the organism in secretion or on cultivation. Dot-blot DNA hybridization assay is useful.

Diagnosis. Detection of cysts or trophozoites in the stool.

Diagnosis. Diagnosis depends on the recovery and identification of gravid proglottids or egg-balls in the stool.

Diagnosis & Treatment. Detection and removal of the worm.

Diagnosis. Diagnosis may be made by the microscopic identification of cysts in solid feces or trophozoites in diarrheic stool. The parasite may be detected in aspirated material of liver abscess. Serologic tests, such as IFA, ELISA, for specific antibodies to E. histolytica are very helpful in diagnosis of invasive amebiasis.

Diagnosis. A definite laboratory diagnosis is made by finding the trypanosomes in the blood, lymph nodes, and bone marrow or spinal fluid. The methods include a direct microscopical examination, cultivation and animal inoculation.

Diagnosis. A definite laboratory diagnosis is made by finding the trypanosomes in the blood, lymph nodes, and bone marrow or spinal fluid. The methods include a direct microscopical examination, cultivation and animal inoculation.

Diagnosis. Detection of oocysts in the stool using modified acid fast staining, indirect fluorescent antibody test or PCR.

Diagnosis. Detection of organisms from bronchoalveolar lavage fluid or sputum by staining (DQ, GMS, toluidine blue, IFA) or PCR. Pulmonary infiltration in chest radiology may support the diagnosis.

Diagnosis. Blood test showing trypanosomes, or xenodiagnosis using cultured bugs.

Diagnosis. Diagnosis is normally accomplished by sampling the perianal and perineal skin with cellulose addhesive tape. It is important to note that multiple samples may be required to confirm the presence of a light infections as well as to conclude that a patient is free of infection.

Diagnosis. Recovery of the eggs in stool samples.

Diagnosis. Detection of eggs in feces.

Diagnosis. Radiological studies, immunoelectrophoresis for the arc 5, or ELISA are useful.

Diagnosis. Diagnosis of alveolar hydatidosis is difficult due to the lacking of protoscolices in the cysts. Radiological studies or ELISA can be helpful.

Diagnosis. The very small eggs can be detected by direct microscopic stool examination.

Diagnosis. Finding of eggs in feces. Ultrasonography and liver scanning can show lesions compatible with the infection. Immunodignosis by ELISA using crude somatic extracts of O.viverrini is available.

Diagnosis. Diagnosis is made by finding the characteristic eggs in feces. Spurious infection must be ruled out by repeated examination. Definitive diagnosis can be made by recovery of adult flukes at surgery or autopsy.

Diagnosis. Definitive diagnosis can be made easily with naked eyes by finding the adult or eggs.

Diagnosis. Detection of amastigotes by biopsy of the liver or spleen confirms the diagnosis. Serology or PCR may support the diagnosis.

Diagnosis. Detection of amastigotes by biopsy of the skin lesion confirms the diagnosis. Serology or PCR may support the diagnosis

Diagnosis. The clinical diagnosis is often based on the patient's history of eating raw meat or clinical symptoms such as fever, facial edema, muscle pain and eosinophilia. Definitive diagnosis can be made by demonstration of encapsulated or free larvae from the compressed muscle samples. The xenodiagnosis is useful in surveys to detect viable larvae. Intradermal test and enzyme-linked immunosorbent assay (ELISA) are also useful.

Diagnosis. The clinical diagnosis is often based on the patient`s history of eating raw fishes, frogs and snakes, as well as the clinical symptoms. In rare cases, the migrating larvae are recovered but histologic diagnosis are also useful. Intradermal test and enzyme-linked immunosorbent assay (ELISA) are applicable.

Diagnosis. Patients with gastric pains with history of eating raw seafoods, gastroscopy should be considered.

Diagnosis. Refer to Metagonimus Species.

Diagnosis. Refer to Metagonimus Species.

Diagnosis. Refer to Metagonimus Species.

Diagnosis. Refer to Metagonimus Species.

Diagnosis. Detection of eggs from the feces, but careful differentiation is required to identify the eggs. The eggs are very small, only 20-25 by 11-15 mm in size, smaller than those of C. sinensis, M. yokogawai, or other heterophyids, except for those of P. summa, and have a very thin and transparent shell. The eggs are not readily detected in routine fecal examinations performed by formalin-ether sedimentation or cellophane thick smear techniques. They may be overlooked or misdiagnosed as an air bubble or other artifacts, especially in thick smears.

Diagnosis. The diagnosis is based on the recovery of the typical eggs.

Diagnosis. Diagnosis is made by finding the eggs from the feces. The eggs require differentiation from another intestinal flukes.

Diagnosis. Identification of eggs by stool examination. Differentiation from other heterophyid flukes and Clonorchis eggs is needed.

Diagnosis. Microscopic identification of eggs in stool or urine is the most practical for the diagnosis. Stool examination should be performed when infection with S. mansoni or S. japonicum is suspected, and urine examination should be performed if S. haematobium is suspected. Eggs can be present in the stool in infections with all Schistosoma species. Tissue biopsy (rectal biopsy for all species and biopsy of the bladder for S. haematobium) may demonstrate eggs when stool or urine examinations are negative. Various immunodiagnostic tests are available including intradermal and ELISA.

Diagnosis. Corneal biosy and corneal scrapings and culture usually permit the correct diagnosis.

Treatment. See W. bancrofti.

Prevention. See W. bancrofti.

Prevention. Avoiding consumption of raw vegetables in affected countries with poor living conditions..

Hae-Jin Jeong

Prevention. Avoiding ingestion of raw fresh-water fish.

Prevention. Avoiding ingestion of raw watercress grown in endemic areas.

Jin Kim

Prevention. Personal cleanliness, destruction of rats and mice, and a well-balanced diet to promote resistance to infection..

Hae-Jin Jeong

Prevention. Personal protection against mosquito bites is the first line of defence against malaria. In addition, travellers should take chemoprophylaxis where appropriate.

Weon-Gyu Kho

Prevention. Personal protection against mosquito bites is the first line of defence against malaria. In addition, travellers should take chemoprophylaxis where appropriate.

Weon-Gyu Kho

Prevention. Personal protection against mosquito bites is the first line of defence against malaria. In addition, travellers should take chemoprophylaxis where appropriate.

Weon-Gyu Kho

Prevention. Personal protection against mosquito bites is the first line of defence against malaria. In addition, travellers should take chemoprophylaxis where appropriate.

Weon-Gyu Kho

Prevention. Compositing and various schedules of storage of human excreta may provide effective methods of ascariasis control by destroying the parasite eggs before the night soil is used.

Chong Yoon Joo

Treatment. Praziquantel is a drug of choice with more than 95% efficiency. Praziquantel is definitely effective in early stage of active cerebral paragonimiasis. Its adverse effects include headache, dizziness, gastrointestinal disturbance, and blurred vision, albeit mild and transient. Triclabenazole is also effective. Any significant side effect has not been reported. In the cases of chronic calcified cerebral paragonimiasis, surgical removal is recommended.

Prevention. Human infection is closely related with eating habits of foods. In many endemic regions, people acquire the infection by eating raw/undercooked freshwater crustaceans. Raw boar meat harboring excysted metacercariae are also infective.

Prevention. Avoid ingestion of raw or undercooked salmon, trout, perch, and pike.

Suk-Il Kim

Prevention. Avoiding the haunts of Simulium by wearing clothing that reduces the area of skin exposed to bites, or by using insecticides and personal insect repellent spray. There is no chemoprophylaxis.

Hae-Seon Nam

Prevention. Health education is mostly important in the community because it is one of the sexually tramsmitted disease. Asymptomatic male carrier must be detected and treated.

Prevention. Chlorization and filtration of drinking water.

Prevention. Pets should be kept free of the parasites. The insects should be adequately controlled. The children must be taken precautions.

Prevention. Environmental sanitation is necessary to prevent water and food contamination. Boiling or filtration of drinking water is a safe and effective way of prevention, and avoidance of consuming contaminated food is essential.

Prevention. Prevention include the reduction of sources of infection, the protection of people from infection, the control of riverine tsetse flies, and chemoprophylaxis with pentamidine.

Prevention. The prevention involves constant supervision to detect new cases, to keep track of the old, and regulate agriculture. Contact between humans and tsetse flies may be broken by the removal of the inhabitants from fly-infested areas to open country. Chemoprophylaxis, repellents, and nets may give some protection to the individual.

Tai Soon Yong

Prevention. Improved personal hygiene, adequate washing of vegetables, and filtration or boiling of drinking water are necessary.

Prevention. Prophylactic medication is effective for immunocompromised hosts.

Sung-Tae Hong

Treatment. Treatment should begin as soon as possible following exposure as it is most effective during the acute stage of the infection. Once the chronic stage is reached, there is no effective treatment; only the related conditions, such as heart disease, can be treated or managed.

Prevention.
1) Avoid sleeping in mud, adobe or thatch houses; 2) Wear thick clothing that reduces the amount of exposed skin, such as heavy long-sleeved shirts, long pants, socks and shoes; 3) Sleep inside screened areas, under a bed net or in an air-conditioned room; 4) Avoid blood transfusions in countries where Chagas disease is endemic.


Min-Ho Choi

Treatment. The treatment of choice for the enterabiasis is mebendazole and albendazole. It should be repeated 2 weeks later. All of the family members should be treated together at the same time.

Prevention. Proper personal hygiene: hand washing, applying ointment, perianal area to avoid dispersal..

Lee, Joon-Sang

Prevention. Proper sanitation practices, appropriate fecal disposal, and personal protection by covering bare feet.

Treatment. Mebendazole or albendazole. It should not be given to pregnant women.


Kyoung Hwan Joo

Prevention. Avoid eating raw snails and loaches.

Prevention. Deworming of dogs and personal hygiene.


Duk-Young Min

Prevention. Deworming of dogs are preventive ways in the endemic regions.


Duk-Young Min

Prevention. There is no special preventive measure.

Prevention. Avoid eating raw or undercooked freshwater fishes.


hyun Park

Prevention. Human infections are generally accidental.

Prevention. Close contact or sexual intercourse with infected person should be avoided.

Prevention. Protection from sandfly bite is essential.


Sung-Tae Hong

Prevention. Protection from sandfly bite is essential.


Sung-Tae Hong

Prevention. Avoiding ingestion of raw or inadequately cooked meat of pigs or wild animals.

Prevention. Avoiding ingestion of untreated water, raw freshwater fishes, tadpoles or snakes.

Importance. Df and Dp produce the most important allergens causing allergic diseases.

Control and Prevention. Cleaning and keeping dry condition in houses are the most important, fundamental factors to control house dust mite populations. Direct control measures include the application of proper acaricides and washing of cover cloth of beds and pillows


Han-Il Ree

Treatment. In acute infection, larvae should be removed by gastroscopy. No effective chemotherapy is available.

Prevention. Avoid eating raw fishes in the endemic areas. Freezing of raw fish under -20℃ for 60 hours kills the larvae.


Kyoung Hwan Joo

Prevention. Refer to Metagonimus Species.

Treatment. Refer to Metagonimus Species.

Jong-Yil Chai

Prevention. Refer to Metagonimus Species.

Treatment. Refer to Metagonimus Species.

Jong-Yil Chai

Prevention. Refer to Metagonimus Species.

Treatment. Refer to Metagonimus Species.

Jong-Yil Chai

Prevention. Refer to Metagonimus species.

Treatment. Refer to Metagonimus species.

Jong-Yil Chai

Prevention. The best way to prevent G. seoi infection is the avoidance of consuming raw or undercooked oysters. In particular, consumption of oysters collected from the endemic areas should be avoided.

Treatment. The treatment can be successfully performed by giving a single oral dose of 10 mg/ kg praziquantel (Distocide?). Albendazole may also be effective against G. seoi infection.

Jong-Yil Chai

Prevention. Ingestion of raw or improperly cooked flesh of snakes or frogs should be avoided.

Treatment. The drug of choice is praziquantel (Distocide®) as a single 10 mg/ kg dose.

Prevention. In endemic areas, raw or insufficiently cooked tadpoles or freshwater fishes should be avoided.

Treatment. Praziquantel (Distocide®) as a single 10 mg/ kg dose taken at bedtime.
Jong-Yil Chai

Jong-Yil Chai

Prevention. Prohibit eating raw, undercooked, or recently salted fish in endemic areas.

Treatment. The drug of choice is praziquantel (Distocide®) as a 10 mg/ kg single dose.
Jong-Yil Chai

Jong-Yil Chai

Prevention. Prevention of schistosomiasis includes (1) elimination of the infection source, (2) protection of snail-bearing waters from contamination with infectious urine or feces, (3) control of snail hosts, and (4) protection of persons from cercariae-infested waters.

Treatment. Praziquantel is now the drug of choice and is given as a single oral dose of 40 mg/ kg in case of S. mansoni and S. haematobium and 20 mg/ kg t.i.d in S. japonicum infection. Oxamniquine has been effective in treating infections caused by S. mansoni in some areas in which praziquantel is less effective.

Soon-Hyung Lee

Prevention. Regular boiling of contact lens and storage cases.

Comments. This amoeba must be differentiated from E. histolytica.

Ho-Joon Shin

Comments. This amoeba must be distinguished from E. histolytica.

Ho-Joon Shin

Comments. Differential diagnosis from heterophyid eggs is necessary.

Sung-Tae Hong

Comments. Differential diagnosis from Fasciola eggs is necessary. Serological cross-reactions with other helminthiases such as clonorchiasis and fascioliasis should be accounted.

Yoon Kong

Comments. Sexual partners should be treated at the same time.

Jae-Sook Ryu

Comments. The structures described in the morphology section are not easily recognizable. Both optimally stained smear and experienced technician are needed for the accurate diagnosis.

Yun-Kyu Park

Comments. Free eggs without sac should be differentiated from the eggs of Hymenolepis diminuta.

Yun-Kyu Park

Comments. There is a non-pathogenic E. dispar, having a same morphology with E. histolytica. It can be distinguished by molecular biological techniques such as PCR.

Tai Soon Yong

Comments. A succession of antigenic variants occur in T. gambiense infection. This phenomenon stimulates the output of large quantities of immunoglobulin from the host, most of it is non-specific IgM, with no affinity for the infecting parasite. It may be useful for the presumptive diagnosis of African trypanosomiasis.

Tai Soon Yong

Comments. The oocysts are not always detectable and repeated examinations of stool may be needed in clinically suspicious patients.

Jae-Ran Yu

Comments. Differential diagnosis from Fasciola hepatica and F. buski is necessary.


Pyung-Rim Chung

Comments. Differential diagnosis between Eurytrema pancreaticum is needed.


Mee-Sun, Ock

Comments. Eggs of the Dicrocoelium dendriticum and E. pancreatum is almost indistinguishable.


Gab-Man Park

Comments. Current sexual partners should be examined and treated also.


Yun-Kyu Park

Comments. Differential diagnosis from the acute food-poisoning is necessary.


Woon-Mok Sohn

Comments. Differential diagnosis from other tissue invading helminths is necessary.


Woon-Mok Sohn

Comments. Differential diagnosis is required from the eggs of other trematodes or cestodes, particularly from those of echinostomatiids, fascioliids, Paragonimus, Diphyllobothrium, etc.

Jong-Yil Chai

Comments. Most cases of granulomatous amoebic encephalitis were diagnosed by postmortem autopsy.

Hyun-Hee Kong


Egg of Clonrochis sinensis. Operculum, shoulder rim and surface wrinkling are distinctive. Length of 28-30 micrometer, width 14-18 micrometer.

Sung-Tae Hong


Egg of Echinostoma hortense in the feces of an infected patient. See the operculum on the top of the egg and the terminal wrinkling at its bottom. x 400.

Jong-Yil Chai


An egg of Metagonimus yokogawai

Tai Soon Yong


An egg ball(or egg sac) of Dipylidium caninum.

Tai Soon Yong


A fertilized egg of Ascaris lumbricoides.

Tai Soon Yong


A fertilized egg of Ascaris lumbricoides.

Tai Soon Yong


A fertilized egg of Ascaris lumbricoides. Two divided cells are seen interior of the egg here.

Tai Soon Yong


Hookworm egg.

Tai Soon Yong


Hookworm egg.

Tai Soon Yong


Clonorchis sinensisegg.

Tai Soon Yong


Matured eggs of Echinostoma hortense, operculated, yellowish brown with wrinkled thickening of shell, and showing the miracidium in egg shell. X 450.

Yong Suk Ryang



Yong Suk Ryang



Yong Suk Ryang


Hookworm eggs in the stool examination from the patient, X450

Yong Suk Ryang


Hookworm, various eggs in the stool examination from the patient, X450

Yong Suk Ryang


Hookworm ova and larva in the stool examination from case, X100

Yong Suk Ryang




Eggs of E. vermicularis (x400) --from 6-year boy.
Cellophane-tape impression showing pinworm ova.

Chong Yoon Joo


Eggs of E. vermicularis (x400) --from 6-year boy.
Cellophane-tape impression showing pinworm ova.

Chong Yoon Joo


Eggs of E. vermicularis (x400) --from 6-year boy.
Cellophane-tape impression showing pinworm ova.

Chong Yoon Joo


Eggs in the metraterm of Plagiorchis muris, unstained. (Hong et al. 1996. J Parasitol 82:647-9).

Sung-Jong Hong


A Neodiplostomum seoulense egg containing a fully matured miracidium with two eyespots. The egg was obtained by embryonating in the laboratory. (Seo et al. 1988. Korean J Parasitol 26:179-188).

Sung-Jong Hong


Egg of Metagonimus yokogawai, unstained. 29 um x 18 um.

Sung-Jong Hong


Egg of Clonorchis sinensis. 29 um x 15 um.

Sung-Jong Hong


Egg of Clonorchis sinensis. 30 um x 16 um.

Sung-Jong Hong


Egg of Clonorchis sinensis. 29 um x 15 um.

Sung-Jong Hong


Egg of Clonorchis sinensis. 29 um x 16 um.

Sung-Jong Hong


An amorphous egg of Clonorchis sinensis longer than the typical ones. 33 um x 16 um.

Sung-Jong Hong


An amorphous egg of Clonorchis sinensis widerer than the typical ones. 27 um x 18 um.

Sung-Jong Hong


Egg of Paragominus westermani. 97 um x 55 um. x400.

Sung-Jong Hong


An egg of Trichuris trichiura. x400.

Sung-Jong Hong


An egg of Trichuris trichiura. x400.

Sung-Jong Hong


An egg of Trichuris trichiura at two-cell stage. x400.

Sung-Jong Hong


An egg of Trichuris trichiura at morular stage. x400.

Sung-Jong Hong


An embyonated egg of Trichuris trichiura. x400.

Sung-Jong Hong


An egg of Ancylostoma duodenale at morular stage. x400.

Sung-Jong Hong


An egg of Ancylostoma duodenale at morular stage. x400.

Sung-Jong Hong


An egg of Trichostrongylus orientalis at morular stage. x400.

Sung-Jong Hong


An egg of Ancylostoma duodenale at morular stage. x400.

Sung-Jong Hong


The embryonated ggs of Enterobius vermicularis.

Sung-Jong Hong


Egg of Echinostoma revolutum.

Woon-Mok Sohn


Egg of Echinostoma hortense.

Woon-Mok Sohn


Egg of Echinostoma cinetorchis.

Woon-Mok Sohn


The egg of Neodiplostomum seoulense

Woon-Mok Sohn


The embryonated egg of Neodiplostomum seoulense

Woon-Mok Sohn


The metacercaria of Holostephanus nipponicus isolated from P. parva

Woon-Mok Sohn


The egg of Pharyngostomum cordatum

Woon-Mok Sohn


The embryonated egg of P. cordatum

Woon-Mok Sohn


Egg of Fasciola hepatica, human case.

Woon-Mok Sohn


Egg of Paragonimus iloktsuenensis.

Woon-Mok Sohn


Embryonated egg of P. iloktsuenensis.

Woon-Mok Sohn


Egg of Toxocara cati.

Woon-Mok Sohn


Embryonated egg of T. cati.

Woon-Mok Sohn


Egg of Capillaria hepatica from feces of cat.

Woon-Mok Sohn


Hookworm egg from feces of cat.

Woon-Mok Sohn


The egg of Clonorchis sinensis from human.

Woon-Mok Sohn


The egg of C. sinensis from a cat.

Woon-Mok Sohn


Egg of Metagonimus sp. from human.

Woon-Mok Sohn


Egg of Pharyngostomum cordatum from a cat.

Woon-Mok Sohn


Egg of Spirometra erinacei from a cat.

Woon-Mok Sohn


Egg of Taenia taeniaeformis from a cat.

Woon-Mok Sohn


Egg of Hymenolepis diminuta from a cat.

Woon-Mok Sohn


Egg of hookworm, Ancylostoma duodenale, from human.

Woon-Mok Sohn


Egg of C. sinensis from human.

Woon-Mok Sohn


Egg of Metagonimus sp. from human.

Woon-Mok Sohn


Egg of Paragonimus westermani from a dog which was experimentally infected.

Woon-Mok Sohn


Egg of Fasciola sp. from human.

Woon-Mok Sohn


Egg of Fasciola sp. from human.

Woon-Mok Sohn


Dicrocoeliid egg from human.

Woon-Mok Sohn


Egg of D. latum from human.

Woon-Mok Sohn


Egg of D. yonagoense from human.

Woon-Mok Sohn


Egg of Spirometra erinacei from a cat, which was experimentally infected.

Woon-Mok Sohn


Egg of Hymenolepis nana from human.

Woon-Mok Sohn


Egg of Taenia sp. from human.

Woon-Mok Sohn


Egg of Plagiorchis sp., which was experimentally incubated.

Woon-Mok Sohn


Egg of Diphyllobothrium latum from human.

Woon-Mok Sohn


SEM view of D. latum egg.

Woon-Mok Sohn


SEM view of D. latum egg.

Woon-Mok Sohn


SEM view of D. yonagoense egg.

Woon-Mok Sohn


Embryonated egg of Spirometra erinacei, which was experimentally incubated and matured.

Woon-Mok Sohn


Metacercariae of Clonorchis sinensis collected from digested fish. The cyst wall is elliptical 0.16-0.20 mm long. Dark granules are in the bladder.

Sung-Tae Hong


A metacercaria of Clonorchis sinensis. The larva in the cyst wall is actively moving. Note two suckers and a excretory bladder filled with dark granules. x150.

Sung-Tae Hong


A metacercaria of Echinostoma hortense encysted in the muscle of a freshwater fish, Odontobutis obscura interrupta. x 40.

Jong-Yil Chai


A redia of Echinostoma hortense, liberated from the freshwater snail, Lymnaea pervia. X 40.

Jong-Yil Chai


Third-stage Anisakis larva, lateral view of tail. Showing the characteristic mucron on posterior end.

Hae-Seon Nam


Encysted larvae of Trichinella spiralis. Intact larvae are seen in teased press preparation of muscle. x200

Hae-Seon Nam


Cysticercus of Taenia solium. A evaginated whole bladder worm from pork. x40

Hae-Seon Nam


Rhabditoidform larva of a hookworm.

Tai Soon Yong


Microfilaria of Dirofilaria immitis.

Tai Soon Yong


A microfilaria of Loa loa. The sheathed microfilariae usually have a diurnal periodicity in the blood.

Tai Soon Yong


Cercaria of Clonorchis sinensis. The cercaria is liberated from its first intermediate host, a fresh water snail.

Tai Soon Yong


Scolex of a sparganum. Sparganum is a larval tapeworm of the genus Spirometra that is common in various canines and felines, causes sparganosis in humans.

Tai Soon Yong


A section of cysticercus showing a solid larva of Cysticercus cellulosae, larval stage of Taenia solium.

Tai Soon Yong


Chigger mite, larva of Leptotrombidium orientale (ventral view of slide-specimen). Chigger mites which are vectors of tsutsugamushi disease feed on blood in the larval stage only.

Tai Soon Yong


Nymph of a hard tick, Ixodes nipponensis, anterior part including capitulum (gnathosoma) of slide-mounted specimen (ventral).

Tai Soon Yong


Larva, nymph and female adult of the European house dust mite (Dermatophagoides pteronyssinus). Ventral view of slide-mounted specimens.

Tai Soon Yong


Third instar larvae and pupae of the house fly (Musca domestica). A pair of the posterior spiracles are seen at the end of the body.

Tai Soon Yong


Cysticerci of Taenia solium liberated from host tissue. Note protruding scoleces.

Tai Soon Yong


Cysticerci of Taenia solium in pig muscle.

Tai Soon Yong


Microfilaria of Brugia malayi. Perpheral blood thick smear and Giemsa srain, X 450.

Yong Suk Ryang


Rhabditiform larva of Strongyloides stercoralis. the larvae found in the fresh faeces of man, X 200.

Yong Suk Ryang


Motile cercaria of Echinostoma hortense under a cover slip, showing lustrous exceretory granules.

Yong Suk Ryang


Miracidium of Echinostoma hortense, hatching start on 10th days of cultivation.

Yong Suk Ryang


Filariform larvae of Ancylostoma duodenale, cultivated soil specimen, X200

Yong Suk Ryang


Anterior part of the filariform larvae of Ancylostoma duodenale showing head part, mouth part and black line of a spear shape, X200

Yong Suk Ryang



Yong Suk Ryang


Cultivated filariform larva of Ancylostoma duodenale, stool specimen from patient, 3 week after the cultured, X40

Yong Suk Ryang


Anterior part of Anisakis Type I larva showing boaring teeth x200

Chong Yoon Joo


Anisakis Type I larva showing ventriculus. x200

Chong Yoon Joo


Posterior part of Anisakis Type I larva showing short tail with mucron. x200

Chong Yoon Joo


Cercaria of Neodiplostomum seoulense, shedded from a planorbid snail, Hippeutis cantori.

Sung-Jong Hong


Miracidium of Neodiplostomum seoulense. Note a crescent-shaped eyespot and the cillia covering surface. 119 um long and 34 um wide. Unstained.

Sung-Jong Hong


Miracidium of Neodiplostomum seoulense, stained by silver impregnation method. Note the epidermal plates arranged in four rows. (Seo et al. 1988. Korean J Parasitol 26:179-188).

Sung-Jong Hong


Metacercaria of Centrocestus armatus, collected from Zacco platypus. 229 um long and 129 um wide. Note circumoral spines arraned like a comb around the oral sucker. (Hong et al. 1989. Korean J Parasitol 27:47-56.)

Sung-Jong Hong


Metacercaria of Heterophyopsis continua. Note the Y-shaped excretory bladder in black.

Sung-Jong Hong


Metacercariae of Metagonimus yokogawai collected from sweetfish. x400.

Sung-Jong Hong


Metacercaria of Clonorchis sinensis collected from Pseudorasbora parva. x400.

Sung-Jong Hong


Metacercaria of Paragonimus iloktsuenensis in a brackish water crab, Sesarma dehaani. x100.

Sung-Jong Hong


A sparganum is penetrating the intestinal wall to the peritoneal cavity in a mouse. x200.

Sung-Jong Hong


A section of sparganum, hematoxylin-eosin stained, shows a thick tegument, subtegumental muscle layer, and calcospherules. The calcospherules appear in shapes with variopus intrastuctures such as concentric circles and stainabilities. x400.

Sung-Jong Hong


A blader, Cysticercus cellulosae, is exposed from the fibrotic capsule.

Sung-Jong Hong


The hooklets on rostellum of Cysticercus cellulosae.

Sung-Jong Hong


The parenchymatous tissue of Cysticercus cellulosae shows thick tegumental syncytium and calcospherules (arrows). Hematoxylin-eosin stained. x400.

Sung-Jong Hong


Cyst wall of Cysticercus cellulosae. Note the thin tegument and the excretory canals dispersed in mesenchymal tissue. Hematoxylin-eosin stained. x400.

Sung-Jong Hong


A section of parenchymatous portion of Cysticercus cellulosae shows invaginated scolex, spiral canal and vestibule. x100.

Sung-Jong Hong


An encysted larva of Trichinella spiralis in muscle. Acetocarmine stained.

Sung-Jong Hong


Two encysted larvae of Trichinella spiralis in muscle. Acetocarmine stained.

Sung-Jong Hong


A rhabditoid larva of Strongyloides stercoralis. Photographed with a microscope with differential interference contrast attachment (DIC). x200. (Hong et al. 1988. Korean J Parasitol 26: 22-6). x200.

Sung-Jong Hong


The filariform larva of Strongyloides stercoralis collected from sputum of a patient. x200. (Hong et al. 1988. Korean J Parasitol 26: 22-6).

Sung-Jong Hong


Hydatid cyst of Echinococcus granulosus demonstrates the three layers of the cyst wall and 2 brood capsules containing multiple protoscoleces. (H&E, 400x).

DY Min/MH Ahn/JS Ryu


Multilocular hydatid cyst of Echinococcus multilocularis (H&E, 400x).

DY Min/MH Ahn/JS Ryu


Metacercaria of Heterophyes nocens from a mullet, Mugil cephalus.

Woon-Mok Sohn


Metacercaria of H. nocens from a goby, Acanthogobius flavimanus.

Woon-Mok Sohn


Heterophyopsis continua metacercaria from a goby, Acanthogobius flavimanus.

Woon-Mok Sohn


Metacercaria of H. continua from a sea perch, Lateolabrax japonicus.

Woon-Mok Sohn


Metacercaria of Pygidiopsis summa from a mullet, Mugil cephalus.

Woon-Mok Sohn


Metacercaria of Stellantchasmus falcatus from a mullet.

Woon-Mok Sohn


Metacercaria of Stictodora fuscatum from a goby.

Woon-Mok Sohn


Metacercariae of Centrocestus armatus in the intestine of pale chub, Zacco platypus.

Woon-Mok Sohn


Metacercaria of C. armatus from a Z. platypus.

Woon-Mok Sohn


Mesocercariae of Gymnophalloides seoi in an oyster.

Woon-Mok Sohn


Mesocercaria of G. seoi isolated from an oyster.

Woon-Mok Sohn


Mesocercaria of G. seoi isolated from an oyster. Semichon's acetocarmine stained.

Woon-Mok Sohn


Metacercariae of Parvatrema timondavidi in a Tapes philippinarum.

Woon-Mok Sohn


Metacercaria of Parvatrema timondavidi isolated from a Tapes philippinarum.

Woon-Mok Sohn


Miracidium of E. hortense.

Woon-Mok Sohn


The epidermal plate of E. hortense miracidium.

Woon-Mok Sohn


The second generation redia of E. hortense.

Woon-Mok Sohn


Cercaria of E. hortense from an experimental lymnaeid snail, Fossaria truncatula.

Woon-Mok Sohn


Metacercariae of E. hortense encysted in the gill of tadpole, which was experimentally challenged with cercariae.

Woon-Mok Sohn


Metacercaria of E. hortense encysted in the muscle of tadpole, which was experimentally challenged with cercariae.

Woon-Mok Sohn


Metacercaria of E. hortense encysted in the muscle of a Squalidus japonicus.

Woon-Mok Sohn


E. cinetorchis larvae in the experimental snail, Hippeutis cantori.

Woon-Mok Sohn


The 2nd generation redia of E. cinetorchis isolated from an experimental snail, Hippeutis cantori.

Woon-Mok Sohn


Metacercaria of E. cinetorchis isolated from an experimental snail, Hippeutis cantori.

Woon-Mok Sohn


The 2nd generation redia of Echinoparyphium recurvatum isolated from an experimental lymnaeid snail, Radix auricularia coreana.

Woon-Mok Sohn


Cercaria of E. recurvatum isolated from an experimental lymnaeid snail, R. auricularia coreana.

Woon-Mok Sohn


Metacercaria of E. recurvatum isolated from an experimental lymnaeid snail, R. auricularia coreana.

Woon-Mok Sohn


Metacercariae of Echinochasmus japonicus from the gill of tadpole, which was experimentally infected with cercariae.

Woon-Mok Sohn


Metacercariae of E. japonicus isolated from Pseudorasbora parva.

Woon-Mok Sohn


The mesocercaria of P. cordatum isolated from a snake

Woon-Mok Sohn


Metacercaria of Clonorchis sinensis isolated from P. parva.

Woon-Mok Sohn


Metacercaria of Clonorchis sinensis isolated from P. parva.

Woon-Mok Sohn


Metacercaria of Clonorchis sinensis isolated from Pungtungia herzi.

Woon-Mok Sohn


Metacercariae of Paragonimus westermani isolated from a crayfish.

Woon-Mok Sohn


Metacercaria of Paragonimus westermani isolated from a crayfish.

Woon-Mok Sohn


A coiled Trichinella spiralis larva in the biopsied muscle of human.

Woon-Mok Sohn


Larva of T. spiralis isolated from the muscle of human.

Woon-Mok Sohn


T. spiralis larva in the muscle of human case, which was biopsied after treatment with flubendazole and albendazole for 10 days. The larvae detected at the same day were uncoiled and did not show the infectivity in mice and a hamster. (Semichon's acetocarmine stained).

Woon-Mok Sohn


T. spiralis larva in the muscle of human case, which was biopsied after treatment with flubendazole and albendazole for 10 days. The larvae detected at the same day were uncoiled and did not show the infectivity in mice and a hamster. (Semichon's acetocarmine stained).

Woon-Mok Sohn


Anterior portion of the 3rd stage larva of Anisakis simplex.

Woon-Mok Sohn


Ventricular portion of the 3rd stage larva of A. simplex.

Woon-Mok Sohn


Tail portion (with a mucron) of the 3rd stage larva of A. simplex.

Woon-Mok Sohn


SEM view of anterior portion of the 3rd stage larva of A. simplex.

Woon-Mok Sohn


SEM view of middle portion of the 3rd stage larva of A. simplex.

Woon-Mok Sohn


SEM view of tail portion of the 3rd stage larva of A. simplex.

Woon-Mok Sohn


Anterior portion of the 4th stage larva of A. simplex.

Woon-Mok Sohn


Ventricular portion of the 4th stage larva of A. simplex.

Woon-Mok Sohn


Tail portion of the 4th stage larva of A. simplex.

Woon-Mok Sohn


SEM view of middle portion of the 4th stage larva of A. simplex.

Woon-Mok Sohn


SEM view of tail portion of the 4th stage larva of A. simplex.

Woon-Mok Sohn


Head-on view of Pseudoterranova decipiens larva from a human case.

Woon-Mok Sohn


Anterior portion of P. decipiens larva from a human case.

Woon-Mok Sohn


Ventricular portion P. decipiens larva from a human case.

Woon-Mok Sohn


Anterior portion of P. decipiens larva from a human case.

Woon-Mok Sohn


Ventricular portion of P. decipiens larva from a human case.

Woon-Mok Sohn


Middle portion of P. decipiens larva from a human case.

Woon-Mok Sohn


Posterior portion of P. decipiens larva from a human case.

Woon-Mok Sohn


The early 3rd stage larva (EL3) of Gnathostoma. nipponicum from a loach imported from China.

Woon-Mok Sohn


The early 3rd stage larva of G. nipponicum from a loach imported from China.

Woon-Mok Sohn


Head bulb of G. nipponicum.

Woon-Mok Sohn


Schematic drawing of G. nipponicum.

Woon-Mok Sohn


The early 3rd stage larva of G. hispidum from a loach imported from China.

Woon-Mok Sohn


Head bulb of G. hispidum.

Woon-Mok Sohn


SEM view of G. hispidum.

Woon-Mok Sohn


Head bulb of G. hispidum.

Woon-Mok Sohn


The advanced 3rd stage larva (AdL3) of G. hispidum in the liver of mouse, which was experimentally infected with EL3.

Woon-Mok Sohn


G. hispidum recovered from a rat, which was experimentally infected.

Woon-Mok Sohn


Head bulb of G. hispidum (AdL3).

Woon-Mok Sohn


SEM view of the head bulb of G. hispidum (AdL3).

Woon-Mok Sohn


Encysted larva of G. hispidum from a Korean viper, Agkistrodon brevicaudus.

Woon-Mok Sohn


G. hispidum from a Korean viper.

Woon-Mok Sohn


Head bulb of G. hispidum from a Korean viper.

Woon-Mok Sohn


SEM view of G. hispidum from a Korean viper.

Woon-Mok Sohn


SEM view of the head bulb of G. hispidum.

Woon-Mok Sohn


Cross sectional view of G. hispidum from a Korean viper, H&E stained.

Woon-Mok Sohn


Cross sectional view of G. hispidum from a Korean viper, H&E stained.

Woon-Mok Sohn


Coracidium of S. erinacei.

Woon-Mok Sohn


SEM view of the coracidium of S. erinacei.

Woon-Mok Sohn


Magnified SEM view of the coracidium of S. erinacei.

Woon-Mok Sohn


TEM view of the coracidium of S. erinacei.

Woon-Mok Sohn


SEM view of the procercoid of Spirometra erinacei.

Woon-Mok Sohn


SEM view of the procercoid of Spirometra erinacei.

Woon-Mok Sohn


SEM view of the microtriches in procercoid of Spirometra erinacei.

Woon-Mok Sohn


Plerocercoid of Spirometra erinacei in the intestinal wall of tadpole which was experimentally infected with procercoid.

Woon-Mok Sohn


A plerocercoid of Spirometra erinacei isolated from an experimental tadpole at 1 day after infection.

Woon-Mok Sohn


A plerocercoid of Spirometra erinacei isolated from an experimental tadpole at 11 day after infection.

Woon-Mok Sohn


Plerocercoids of Spirometra erinacei (spargana) recovered from an experimental tadpole at 30 day after infection.

Woon-Mok Sohn


A spargana collected from snakes.

Woon-Mok Sohn


SEM view of a 3-day-old plerocercoid of Spirometra mansonoides.

Woon-Mok Sohn


Frontal view of 3-day-old plerocercoid of Sprimetra mansonoides by SEM.

Woon-Mok Sohn


SEM view of a 10-day-old plerocercoid.

Woon-Mok Sohn


Microtriches in a 10-day-old plerocercoid.

Woon-Mok Sohn


TEM view of a plerocercoid of Spirometra erinacei.

Woon-Mok Sohn


Microphalloides japonicus excysted metacercaria from Sesarma dehaani.

Woon-Mok Sohn


Excysted metacercaria of Exorchis oviformis.

Woon-Mok Sohn


Clonorchis sinensis adult worms (about 2900) recovered from a heavy infected case during surgery of gall bladder.

Sung-Tae Hong


A destroyed Clonorchis sinensis by praziquantel treatment. Only anterior part and the body margin remained.

Sung-Tae Hong


Fresh adult worms of Clonorchis sinensis recovered from experimentally infected rabbits. Worms in the right side are 4 weeks old and those in the left are 12 weeks old. The worm is grossly red but the intestinal ceca and distal uterus are dark.

Sung-Tae Hong


Adult Clonorchis sinensis, acetocarmine stained. Its uterus is full of eggs, ovary and two tandem branched testes are seen well.

Sung-Tae Hong


An adult fluke of Echinostoma hortense recovered from a patient, acetocarmine stained. x 10.

Jong-Yil Chai


Numerous adult flukes of Echinostoma hortense recovered from a patient living in an endemic area.

Jong-Yil Chai


An adult fluke of Echinostoma cinetorchis in the feces of an infected person. See that the anterior testis has been displaced a little from its original position. x 10.

Jong-Yil Chai


An adult fluke of Echinostoma cinetorchis recovered from an experimentally infected rat. Note that the 2 testes disappeared in this specimen. x 10.

Jong-Yil Chai


Buccal capsule of adult worm of Ancylostoma caninum. Ancylostoma caninum is a common parasite of dogs. A wide buccal capsule bearing three pairs of ventral teeth is a diagnostic character of the species. The larval stage has been reported as causing creeping eruption to human.

Hae-Seon Nam


A scolex of Taenia solium. The scolex is roughly quadrate, with a diameter of about 1mm, has four large, deeply cupped suckers and a conspicuous, rounded rostellum, armed with a double row of large and small hooks, numbering 22 to 36 and measuring 140 to 200 um and 100 to 150 um, respectively, in length. x40

Hae-Seon Nam


Transverse section of Ascaris lumbricoides lips. There are 3 lips observed.

Tai Soon Yong


Male reproductive organ of Trichostrongylus orientalis. Brown colored paired spicules are characteristic features.

Tai Soon Yong


Adult worm of Dicrocoelium dendriticum. Male and female reproductive systems are reversely located compared with other trematodes.

Tai Soon Yong


Adult worm of Opisthorchis viverinii.

Tai Soon Yong


Adult worm of Opisthorchis felineus.

Tai Soon Yong


Adult worm of Paragonimus westermani.

Tai Soon Yong


Adult worm of Eurytrema pancreaticum.

Tai Soon Yong


Adult worm of Metagonimus yokogawai

Tai Soon Yong


Scolex of Diphyllobothrium latum.

Note the bothria, two deep dorsoventral suctorial grooves, which are typical structures of the pseudophyllidean tapeworm.

Tai Soon Yong


Scolex of Hymenolepis nana.

Tai Soon Yong


Scolex of Hymenolepis diminuta.

Tai Soon Yong


Proglottid of Taenia saginata.

Tai Soon Yong


Adult worm of Echinostoma hortense.

Tai Soon Yong


Adult worm of Eurytrema pancreaticum.

Tai Soon Yong


Hard tick (Dermacentor sp.), female (dorsal view)

Tai Soon Yong


European house dust mite (Dermatophagoides pteronyssinus), male adult (ventral side of slide-specimen). This species and American house dust mite (Dermatophagoides farinae) are the most important, cosmopolitan species among house dust mites (Pyroglyphidae).

Tai Soon Yong


Female of Tabanus sp. (Diptera, Tabanidae), lateral view. Tabanids are large, stout and colorful insects which transmit loasis.

Tai Soon Yong


Female of Demodex folliculorum (Acari, Demodicidae), a ventral view. This mite is extra-ordinarily elongated.

Tai Soon Yong


A house fly (Musca domestica) laying eggs. Masses of milky white, banana shaped eggs are seen.

Tai Soon Yong


Pubic louse(Phthirus pubis) female (dorsal view of slide-mounted specimen), belonging to Phthiridae, Anoplura.

Tai Soon Yong


Spicule (male genital organ) of Ascaris lumbricoides.

Tai Soon Yong


A Ascaris lumbricoides male adult. This worm was obtained from vomitus of an infected person.

Tai Soon Yong


Posterior part of the male worm of Ancylostoma duodenale showing postero-lateral copulatory in copuratory bursa, X100

Yong Suk Ryang


Posterior part of the male worm of Ancylostoma duodenale showing postero-lateral copulatory in copulatory bursa, X40

Yong Suk Ryang


Anterior part of the female worm of Ancylostoma duodenale showing head part, dorsal view, ventral teeth, dorsal teeth, and groove in capsule wall, X100

Yong Suk Ryang


Anterior part of the female worm of Ancylostoma duodenale showing head part, dorsal view, ventral teeth, dorsal teeth, and groove in capsule wall, X40

Yong Suk Ryang


Eurytrema pancreaticum : from pancreas of cattle, Acetocarmine stain, X40

Yong Suk Ryang


Clonorchis sinensis : from liver of rabbit, Acetocarmine stain, X40

Yong Suk Ryang


Diphyllobothrium latum: Rosette shape uteri in the gravid proglittids stained with Aceto-carmine solution, X20

Yong Suk Ryang


Diphyllobothrium latum : Rosette-shape uteri in the gravid proglottids stained with Aceto-carmine solution, X 40

Yong Suk Ryang


Hymenolepis nana : Anterior part of scolex, Acetocarmine stain, X 450

Yong Suk Ryang


Hymenolepis nana : midle part of gravid proglottids, Acetocarmine stain, X200

Yong Suk Ryang


Hymenolepis nana : Midle part of gravid proglottids, Acetocarmine stain, X450

Yong Suk Ryang


Centrocestus armatus : Semicons acetocarmine stain, X 450

Yong Suk Ryang


Centrocestus armatus : Head part of collar spine, Acetocarmine stain, X450

Yong Suk Ryang






Cross section of adult A. lumbricoides male

Chong Yoon Joo


Cross section of A. lumbricoides female

Chong Yoon Joo


E. vermicularis (male adult) xl00

Chong Yoon Joo


E. vermicularis adult(female) showing esophageal bulb. x200

Chong Yoon Joo


Anterior part of E. vermicularis (female) showing cephalic alae. x200

Chong Yoon Joo


Tail part of A. cantonensis(male) showing spicule and bursa. x200

Chong Yoon Joo


Posterior part of N. americanus(male) showing dorsal ray and spicule. x200

Chong Yoon Joo


Magnigication of dorsal ray in N. americanus (male). x400

Chong Yoon Joo


Posterior part of A. duodenale(male) showing dorsal ray. x200

Chong Yoon Joo


Magnigication of dorsal ray in A. duodenale(male). x400

Chong Yoon Joo


Posterior end of N. americanus(female) x200

Chong Yoon Joo


Posterior end of A. duodenale(female) showing mucron x200

Chong Yoon Joo


Plagiorchis muris adult worm collected from a naturally infected human, 2.9 mm long and 0.9 mm wide. (Hong et al. 1996. J Parasitol 82:647-9).

Sung-Jong Hong


Centorcestus armatus, adult worm, recovered from experimental rat.
326 um long and 197 um wide.

Sung-Jong Hong


Neodiplostomun seoulense, lateral view, recovered from an experimental rat. Acetocarmine stained.

Sung-Jong Hong


Heterophyopsis continua, adult worm, recovered from experimental chick. 2.22 mm long by 0.27 mm wide. Acetocarmine stained.(Hong et al. 1990. Korean J Parasitol 28:53-62.)

Sung-Jong Hong


Stellantchasmus falctus collected from a naturally infected man.

Sung-Jong Hong


Metagonimus yokogawai, adult worm. Acetocarmine stained.

Sung-Jong Hong


Clonorchis sinensis collected from a patient.

Sung-Jong Hong


Clonorchis sinensis collected from a patient.

Sung-Jong Hong


Paragonimus westermani, adult worm. x4.

Sung-Jong Hong


The scolex of Taenia saginata shows four muscular suckers and the rostellum without a hooklet.

Sung-Jong Hong


The scolex of Taenia solium shows four muscular suckers and the rostellum with hooklets.

Sung-Jong Hong


A mature proglottid of Taenia solium, acetocarmine stained. Note an accessory ovarian lobe in between two ovarian lobes.

Sung-Jong Hong


The scolex of Hymenolepis nana shows suckers and an invaginated rostellum. x100.

Sung-Jong Hong


A mature proglottid of Dipylidium caninum contains bilaterally two sets of reproductive system. x100.

Sung-Jong Hong


Trichuris trichiura, male.

Sung-Jong Hong


Stichosome of Trichuris trichiura.

Sung-Jong Hong


Posterior part of male Trichuris trichiura.

Sung-Jong Hong


Posterior part of female Trichuris trichiura.

Sung-Jong Hong


The transitional part leading the anterior slender part to the posterior thick part containing reproductive organs in female Trichuris trichiura. The vagina opens at this part.

Sung-Jong Hong


An oblique section of stichosome shows a chain of stichocytes in Trichuris trichiura. x400.

Sung-Jong Hong


A parasitic female of Strongyloides stercoralis. x100.

Sung-Jong Hong


The transient junction of esophagus (left) to intestine, Strongyloides stercoralis. Photographed with a microscope with differential interference contrast attachment (DIC). x200. (Hong et al. 1988. Korean J Parasitol 26: 22-6).

Sung-Jong Hong


Esophagus of Strongyloides stercoralis. x200.

Sung-Jong Hong


An intra-uterine egg of parasitic Strongyloides stercoralis. Photographed with a microscope with differential interference contrast attachment (DIC). x200. (Hong et al. 1988. Korean J Parasitol 26: 22-6).

Sung-Jong Hong


Tail part of parasitic Strongyloides stercoralis. x200.

Sung-Jong Hong


The copulatory bursa of Ancylostoma duodenale shows a dorsal costa (center).

Sung-Jong Hong


Buccal cavity of Ancylostoma duodenale.

Sung-Jong Hong


Buccal cavity of Necator americanus.

Sung-Jong Hong


Anterior and posterior parts of female Enterobius vermicularis.

Sung-Jong Hong


A cross section of female Enterobius vermicularis at midgut level shows lateral alae, intestine and intra-uterine eggs. H & E stained. x200.

Sung-Jong Hong


Tangled mass of Ascaris lumbricoides.

Sung-Jong Hong


Phthirus pubis.

Sung-Jong Hong


Scolex of Hymenolepis nana showing 2 suckers and rostellum with hooks(A). Mature proglottids have 3 testes (B) (Carmine stain).

DY Min/MH Ahn/JS Ryu


Adult of Echinococcus granulosus showing a scolex and 3 proglottids (immature, mature and gravid)(Carmine stain).

DY Min/MH Ahn/JS Ryu


H. nocens from a cat.

Woon-Mok Sohn


Ventral sucker and gonotyl (genital sucker) of H. nocens.

Woon-Mok Sohn


H. nocens from a cat. Semichon's acetocarmine stained.

Woon-Mok Sohn


H. nocens from human. Semichon's acetocarmine stained.

Woon-Mok Sohn


H. continua collected from a cat. Semichon's acetocarmine stained.

Woon-Mok Sohn


Pygidiopsis summa collected from a cat. Semichon's acetocarmine stained.

Woon-Mok Sohn


P. summa recovered from a dog, which was experimentally infected with metacercariae. Semichon's acetocarmine stained.

Woon-Mok Sohn


Stellantchasmus falcatus collected from a cat.

Woon-Mok Sohn


S. falcatus collected from a cat. Semichon's acetocarmine stained.

Woon-Mok Sohn


Stictodora fuscatum recovered from a cat which was experimentally infected with metacercariae. Semichon's acetocarmine stain.

Woon-Mok Sohn


Centrocestus armatus recovered from a mouse, which was experimentally infected with metacercariae.

Woon-Mok Sohn


Metagonimus yokogawai recovered from a hamster which was experimentally infected with metacercariae. Semichon's acetocarmine stain.

Woon-Mok Sohn


Gymnophalloides seoi recovered from a mouse, which was experimentally infected with metacercariae.

Woon-Mok Sohn


G. seoi recovered from a mouse, which was experimentally infected with metacercariae. Semichon's acetocarmine stained.

Woon-Mok Sohn


P. timondavidi recovered from a mouse, which was experimentally infected with metacercariae.

Woon-Mok Sohn


P. timondavidi recovered from a mouse, which was experimentally infected with metacercariae. Semichon's acetocarmine stained.

Woon-Mok Sohn


E. revolutum collected from a cat. Semichon's acetocarmine stained.

Woon-Mok Sohn


E. revolutum collected from a rat. Semichon's acetocarmine stained.

Woon-Mok Sohn


E. revolutum showing te head crown.

Woon-Mok Sohn


E. hortense recovered from a rat, which was experimentally infected with metacercariae.

Woon-Mok Sohn


E. hortense adult worms collected from human after treatment with praziquantel.

Woon-Mok Sohn


E. hortense from human. Semichon's acetocarmine stained.

Woon-Mok Sohn


E. hortense collected from a cat. Semichon's acetocarmine stained.

Woon-Mok Sohn


E. hortense recovered from a rat, which was experimentally infected with metacercariae. Semichon's acetocarmine stained.

Woon-Mok Sohn


E. cinetorchis with two testes recovered from a rat, which was experimentally infected with metacercariae. Semichon's acetocarmine stained.

Woon-Mok Sohn


E. cinetorchis with one testis recovered from a rat, which was experimentally infected with metacercariae. Semichon's acetocarmine stained.

Woon-Mok Sohn


E. cinetorchis with one dislocated-testis recovered from a rat, which was experimentally infected with metacercariae. Semichon's acetocarmine stained.

Woon-Mok Sohn


E. cinetorchis recovered from an experimentally infected rat. Testis is not seen. Semichon's acetocarmine stained.

Woon-Mok Sohn


E. recurvatum recovered from an experimentally infected duck. Semichon's acetocarmine stained.

Woon-Mok Sohn


E. recurvatum recovered from an experimentally infected duck. Semichon's acetocarmine stained.

Woon-Mok Sohn


Schematic drawing of E. recurvatum.

Woon-Mok Sohn


E. recurvatum recovered from a rat. Semichon's acetocarmine stained.

Woon-Mok Sohn


Head crown and collar spines of E. recurvatum.

Woon-Mok Sohn


E. japonicus recovered from an experimentally infected dog. Semichon's acetocarmine stained.

Woon-Mok Sohn


E. japonicus recovered from a cat. Semichon's acetocarmine stained.

Woon-Mok Sohn


P. cordatum collected from a cat. Semichon's acetocarmine stained.

Woon-Mok Sohn


Transverse section of Fasciola hepatica.

Woon-Mok Sohn


Transverse section of Fasciola hepatica showing multiple intestinal lumen.

Woon-Mok Sohn


Eurytrema pancreaticum collected from a cattle.Semichon's acetocarmine stained.

Woon-Mok Sohn


Clonorchis sinensis collected from a naturally infected cat. Semichon's acetocarmine stained.

Woon-Mok Sohn


C. sinensis collected from a naturally infected cat. Semichon's acetocarmine stained.

Woon-Mok Sohn


Plagiorchis muris collected from a naturally infected cat. Semichon's acetocarmine stained.

Woon-Mok Sohn


P. muris collected from a naturally infected rat. Semichon's acetocarmine stained.

Woon-Mok Sohn


The immature worm of Paragonimus westermani from a naturally infected cat.

Woon-Mok Sohn


P. iloktsuenensis recovered from an experimental cat. Semichon's acetocarmine stained.

Woon-Mok Sohn


Adult male of Ascaris lumbricoides.

Woon-Mok Sohn


Adult female of A. lumbricoides.

Woon-Mok Sohn


Mating adults of A. lumbricoides.

Woon-Mok Sohn


Male A. lumbricoides from the stomach of Korean woman.

Woon-Mok Sohn


Three scolices of D. latum from human.

Woon-Mok Sohn


Mature or gravid proglottid of D. latum from human. Semichon's acetocarmine stained.

Woon-Mok Sohn


Mature or gravid proglottid of D. latum from human. Semichon's acetocarmine stained.

Woon-Mok Sohn


Mature or gravid proglottids of D. latum from a human case, Semichon's acetocarmine stained.

Woon-Mok Sohn


Sectional view of D. latum mature proglottid, H&E stained.

Woon-Mok Sohn


SEM view of the scolex of Spirometra erinacei, lateral side.

Woon-Mok Sohn


SEM view of the scolex of Spirometra erinacei, frontal view.

Woon-Mok Sohn


SEM view of the microtriches on the anterior portion of scolex.

Woon-Mok Sohn


SEM view of the microtriches in the mid-portion of scolex.

Woon-Mok Sohn


SEM view of the microtriches on the neck portion and the lower proglottids.

Woon-Mok Sohn


Gravid proglottid of Spirometra erinacei, Semichon's acetocarmine stained.

Woon-Mok Sohn


Microphalloides japonicus adult from an experimental rat.

Woon-Mok Sohn


Exorchis sp. from a catfish.

Woon-Mok Sohn


Exorchis sp. from a catfish.

Woon-Mok Sohn


Pseudexorchis major from a catfish.

Woon-Mok Sohn


Pseudexorchis major from a catfish.

Woon-Mok Sohn


Carassotrema koreanum from Culter brevicauda.

Woon-Mok Sohn


Impression smeared specimen of the lung of an immune-suppressed rat, showing numerous cystic or trophic forms of Pneumocystis carinii. DQ stained, x1500.

Sung-Tae Hong


Balantidium coli cyst in a stool specimen, a kidney bean-shaped macronucleus is observed.

Tai Soon Yong


TEM of in vitro-derived cyst of Giardia lamblia (left panel), TEM of a faecal originated cyst of Giardia lamblia(right panel)

Tai Soon Yong


Cyst of Entamoeba histolytica, 5-20 ㎛ in size. Chromatoid bodies are often present with thick rodlike masses. The number of nuclei is 1-4.

Tai Soon Yong


Oocyst of Cryptosporidium parvum. Fecal smear stained with modified acid fast method. 5 ㎛.

Jae-Ran Yu


Oocysts of Cryptosporidium parvum labeled by indirect fluorescent antibody test using oocyst wall specific monoclonal antibody (CMYL30).

Jae-Ran Yu


Oocysts of Cryptosporidium parvum stained with monoclonal antibody (CMYL30) and DAPI. Blue dots in the oocysts are sporozoites stained with DAPI.

Jae-Ran Yu


Cyst of Entamoeba histolytica showing a large nucleus with centrally located small karyosome (I-H stain, 1000 x).

DY Min/MH Ahn/JS Ryu


Cyst of Entamoeba coli showing 7 nuclei (Iodine stain, 1000x).
B. Cyst of Entamoeba coli showing 7 nuclei (I-H stain, 1000x).

DY Min/MH Ahn/JS Ryu


Cyst of Endolimax nana showing 2 nuclei with large karyosome (I-H stain, 1000x).

DY Min/MH Ahn/JS Ryu


Cyst of Iodamoeba butschlii showing a large glycogen vacuole (I-H stain, 1000x).

DY Min/MH Ahn/JS Ryu


Cyst of Giardia lamblia showing ellipsoidal shape with 2 nuclei and curved axoneme (Iodine stain, 1000x).

DY Min/MH Ahn/JS Ryu


Cyst of Chilomastix mesnili showing lemon shape with a single nucleus and curved cytostomal fibril (I-H stain, 1000x).

DY Min/MH Ahn/JS Ryu


Amastigotes of Leishmania donovani are seen in an impression smear. The nuclei of L. donovaniis are clearly visible (Giemsa stain, 1000x).

DY Min/MH Ahn/JS Ryu


A section of liver tissue from a case of visceral leishmaniasis. Kupffer cells containing many amastigotes are seen. (H&E, 1000x).

DY Min/MH Ahn/JS Ryu


Trypanosoma cruzi amastigotes are seen in the section of cardiac muscle (H&E, 1000x).

DY Min/MH Ahn/JS Ryu


Cyst of Pneumocystis carinii (A) (Toluidine blue stain, 1000x).

DY Min/MH Ahn/JS Ryu


In smear of rat lung, cyst containing intracystic bodies is seen. The wall of the cyst is not stained with Giemsa, but the intracystic bodies are clearly seen (Giemsa stain, 1000x).

DY Min/MH Ahn/JS Ryu


Cyst of Pneumocystis carinii (C) (Gomori stain, 1000x).

DY Min/MH Ahn/JS Ryu


Oocyst of Isospora sp. (400x).

DY Min/MH Ahn/JS Ryu


Oocyst of Cryptosporidium parvum (A) (Ziehl-Neelsen stain, 1000x).

DY Min/MH Ahn/JS Ryu


Oocyst of Cryptosporidium parvum (B) (Fluorescent antibody test, 1000x).

DY Min/MH Ahn/JS Ryu


A promstigote of Leishmania major in culture media. DQ stained, x1500.

Sung-Tae Hong


TEM photograph of a trophic form Pneumocystis carinii, which is encysted by the carbohydrate layer. x7000.

Sung-Tae Hong


TEM photomicrograph of a trophic form Pneumocystis carinii. x7000.

Sung-Tae Hong


Smear of bronchoalveolar lavage fluid of Pneumocystis carinii pneumonia. The mass is an alveolar cavity material most of which is trophic organisms. Violet dots are nuclei. DQ stained, x1500.

Sung-Tae Hong


Trophozoite stage from culture of Entamoeba histolytica. The living trophozoites vary in size from about 10 to 60 um in diameter, depending on their degree of activity and various other conditions. The nucleus is spherical, with a diameter about one-fifth or one-sixth
that of the entire ameba. It contains a small, distinct central karyosome surrounded by an unstained "halo". Iron-Hematoxylin stain x400

Hae-Seon Nam


Trophozoites from culture of Giardia lamblia. The living trophozoite is rounded anteriorly, pointed posteriorly, and convexed dorsally because of vetral sided sucking disc. The size of the trophozoite varies within wide limits (9 to 21 um in length by 5 to 15 um in breadth and 2 to 4 um in thickness). The four pairs of flagella arise from superficial organelles on the ventral side of the body. x400

Hae-Seon Nam


Plasmodium ovale trophozoite in a red blood cell with fimbriated edges.

Tai Soon Yong


Trophozoite of Acanthamoeba sp., Korean isolate YM-2 demonstrating characteristic morhological features, a distrinct nucleolus, many vacuoles and spine-like pseudopodia.

Tai Soon Yong


A scanning electromicrograph of Acanthamoeba sp., Korean isolate YM-4 showing a typical morphological characteristics of Acanthamoeba trophozoite.

Tai Soon Yong


Trophozoites of Giardia lamblia. Two symmetric nuclei, a median body, and 4 paired flagella are seen.

Tai Soon Yong


Transmission electron micrograph of Giardia lamblia trophozoite (left panel). Enlarged TEM figure showing an adhesive disc of trophozoite (right panel)

Tai Soon Yong


Live trophozoites of Entamoeba histolytica. Note the extending pseudopodia from the ectoplasm.

Tai Soon Yong


Cultured Entamoeba histolytica trophozoite.

Tai Soon Yong


P. falciparum, ring form, Diff-Quik stain, 1000X, Guinea Bissau, M/64, 1997.7

Weon-Gyu Kho


P. falciparum, ring form, Diff-Quik stain, 1000X, Guinea Bissau, M/64, 1997.7

Weon-Gyu Kho


P. vivax, early trophozoite, Diff-Quik stain, 1000X, ROK, M/21, 1999.5

Weon-Gyu Kho


P. vivax, early trophozoite, Diff-Quik stain, 1000X, ROK, M/21, 1999.5

Weon-Gyu Kho


P. vivax, early trophozoite, Diff-Quik stain, 1000X, ROK, M/21, 1999.5

Weon-Gyu Kho


P. vivax, late trophozoite, Diff-Quik stain, 1000X, ROK, M/21, 1999.6

Weon-Gyu Kho


P. vivax, late trophozoite, Diff-Quik stain, 1000X, ROK, M/22, 1999.5

Weon-Gyu Kho


P. vivax, late trophozoite, Diff-Quik stain, 1000X, ROK, M/22, 1999.5

Weon-Gyu Kho


P. vivax, late trophozoite, Diff-Quik stain, 1000X, ROK, M/22, 1999.5

Weon-Gyu Kho


P. vivax, late trophozoite, Diff-Quik stain, 1000X, ROK, M/21, 1999.6

Weon-Gyu Kho


P. vivax, late trophozoite, Diff-Quik stain, 1000X, ROK, M/21, 1999.6

Weon-Gyu Kho


P. vivax, ring form, Diff-Quik stain, 1000X, ROK, M/21, 1999.5

Weon-Gyu Kho


P. vivax, ring form, Diff-Quik stain, 1000X, ROK, M/21, 1999.5

Weon-Gyu Kho


P. vivax, ring form, Diff-Quik stain, 1000X, ROK, M/22, 1999.5

Weon-Gyu Kho


P. vivax, ring form, Diff-Quik stain, 1000X, ROK, M/22, 1999.5

Weon-Gyu Kho


P. vivax, ring form, Diff-Quik stain, 1000X, ROK, M/21, 1999.6

Weon-Gyu Kho


P. vivax, ring and trophozoite, Diff-Quik stain, 1000X, ROK, M/21, 1999.6

Weon-Gyu Kho


P. vivax, ring form, Diff-Quik stain, 1000X, ROK, M/21, 1999.6

Weon-Gyu Kho


Trophozoite of Entamoeba histolytica. The nucleus is characterized by the presence of a small, compact, centrally located karyosome (I-H stain, 1000 x). B. Cultured trophozoite shows pseudopodia.

DY Min/MH Ahn/JS Ryu


Trophozoite of Giardia lamblia showing pear-shaped with 2 nuclei and 2 axoneme (I-H stain, 1000x). B. Trophozoite of Giardia lamblia showing 2 nuclei, axoneme and flagella (Giemsa stain, 1000x).

DY Min/MH Ahn/JS Ryu


Epimastigote of Trypanosoma sp. showing a nucleus (Giemsa stain, 1000x).

DY Min/MH Ahn/JS Ryu