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''Strongyloides stercoralis'' is a human pathogenic parasitic roundworm causing the disease strongyloidiasis. Its common name is threadworm. In the UK and Australia, however, the term ''threadworm'' can also refer to nematodes of the genus ''Enterobius'', otherwise known as pinworms. The ''Strongyloides stercoralis'' nematode can parasitize humans. The adult parasitic stage lives in tunnels in the mucosa of the small intestine. The genus ''Strongyloides'' contains 53 species, and ''S. stercoralis'' is the type species. ''S. stercoralis'' has been reported in other mammals, including cats and dogs. However, it seems that the species in dogs is typically not ''S. stercoralis'', but the related species ''S. canis''. Non-human primates are more commonly infected with ''S. fuelleborni'' and ''S. cebus'', although ''S. stercoralis'' has been reported in captive primates. Other species of ''Strongyloides'', naturally parasitic in humans, but with restricted distributions, are ''S. fuelleborni'' in central Africa and ''S. kellyi'' in Papua New Guinea. ==Geographic distribution== ''S. stercoralis'' has a very low prevalence in societies where fecal contamination of soil or water is rare. Hence, it is a very rare infection in developed economies. In developing countries, it is less prevalent in urban areas than in rural areas (where sanitation standards are poor). ''S. stercoralis'' can be found in areas with tropical and subtropical climates. Strongyloidiasis was first described in the 19th century in French soldiers returning home from expeditions in Indochina. Today, the countries of the old Indochina (Vietnam, Cambodia, and Laos) still have endemic strongyloidiasis, with the typical prevalences being 10% or less. Regions of Japan used to have endemic strongyloidiasis, but control programs have eliminated the disease. Strongyloidiasis appears to have a high prevalence in some areas of Brazil and Central America. It is endemic in Africa, but the prevalence is typically low (1% or less). Pockets have been reported from rural Italy, but current status is unknown. In the Pacific islands, strongyloidiasis is rare, although some cases have been reported from Fiji. In tropical Australia, some rural and remote Australian Aboriginal communities have very high prevalences of strongyloidiasis. In some African countries (e.g., Zaire), ''S. fuelleborni'' was more common than ''S. stercoralis'' in parasite surveys from the 1970s, but current status is unknown. In Papua New Guinea, ''S. stercoralis'' is endemic, but prevalence is low. However, in some areas, another species, ''S. kellyi'', is a very common parasite of children in the New Guinea Highlands and Western Province.〔 Knowledge of the geographic distribution of strongyloidiasis is of significance to travelers who may acquire the parasite during their stays in endemic areas. Because strongyloidiasis is transmittable by textiles, such as bedclothes and clothing, care must be taken never to use hotel bed sheets in endemic areas. Personal sleeping bags and using plastic slippers when showering are very important when travelling in tropical regions. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Strongyloides stercoralis」の詳細全文を読む スポンサード リンク
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