Medical Academy named after S.I. Georgievsky of Vernadsky CFU

-5- SCHISTOSOMES

Prepared by – Mehak Mehla
Scientific Leader – Svetlana Smirnova

flukes. They are parasitic flatworms responsible for a highly significant

group of infections in humans termed schistosomiasis, which is considered by the World Health Organization as the second-most socioeconomically devastating parasitic disease (after malaria), with hundreds of millions infected worldwide

Geographical

distribution

Africa, Brazil, Cambodia, the Caribbean, China, Corsica, Indonesia, Laos, the Middle East, the Philippines, Suriname, and Venezuela.[22] There had been no cases in Europe since 1965, until an outbreak occurred on Corsica

GEOGRAPHICAL DISTRIBUTION

belongs to the group of blood flukes (Schistosoma). The adult

lives in the blood vessels (mesenteric veins) near the human intestine. It causes intestinal schistosomiasis (similar to S. japonicum, S. mekongi, S. guineensis, and S. intercalatum). Clinical symptoms are caused by the eggs. As the leading cause of schistosomiasis in the world, it is the most prevalent parasite in humans.

Schistosoma mansoni is a water-borne parasite of humans, and belongs to the group of blood flukes (Schistosoma). The adult lives in the blood vessels (mesenteric veins) near the human intestine. It causes intestinal schistosomiasis (similar to S. japonicum, S. mekongi, S. guineensis, and S. intercalatum). Clinical symptoms are caused by the eggs. As the leading cause of schistosomiasis in the world, it is the most prevalent parasite in humans.

and ~150 µm diameter on average. They have pointed spines towards

the broader base on one side, i.e. lateral spines

examination of parasite eggs in stool. A staining method called

Kato-Katz technique is used for stool examination. It involves methylene blue-stained cellophane soaked in glycerine or glass slides.] A bit costlier technique called formalin-ether concentration technique (FECT) is often used in combination with the direct faecal smear for higher accuracy. Serological and immunological tests are also available.

digenetic trematode, belonging to a group (genus) of blood flukes

(Schistosoma). It is found in Africa and the Middle East. It is the major agent of schistosomiasis, the most prevalent parasitic infection in humans

for eggs. In chronic infections, or if eggs are difficult

to find, an intradermal injection of schistosome antigen to form a wheal is effective in determining infection. Alternatively diagnosis can be made by complement fixation tests.[28] As of 2012, commercial blood tests included ELISA and an Indirect immunofluorescence test, but these have low sensitivity ranging from 21% to 71%

one primate (Human), two insectivores and three artiodactyls and therefore

it can be considered a true zoonosis.

Schistosoma japonicum is an important parasite and one of the major infectious agents of schistosomiasis.This parasite has a very wide host range, infecting at least 31 species of wild mammals, including 9 carnivores, 16 rodents, one primate (Human), two insectivores and three artiodactyls and therefore it can be considered a true zoonosis.

most practical method for 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.