''Strongyloides'' (from Greek ''strongylos'', round, + ''eidos'', resemblance), anguillula, or threadworm is a genus of small

nematode The nematodes ( or ; ; ), roundworms or eelworms constitute the phylum Nematoda. Species in the phylum inhabit a broad range of environments. Most species are free-living, feeding on microorganisms, but many are parasitic. Parasitic worms (h ...

parasites, belonging to the family Strongylidae, commonly found in the

small intestine The small intestine or small bowel is an organ (anatomy), organ in the human gastrointestinal tract, gastrointestinal tract where most of the #Absorption, absorption of nutrients from food takes place. It lies between the stomach and large intes ...

mammal A mammal () is a vertebrate animal of the Class (biology), class Mammalia (). Mammals are characterised by the presence of milk-producing mammary glands for feeding their young, a broad neocortex region of the brain, fur or hair, and three ...

s (particularly

ruminant Ruminants are herbivorous grazing or browsing artiodactyls belonging to the suborder Ruminantia that are able to acquire nutrients from plant-based food by fermenting it in a specialized stomach prior to digestion, principally through microb ...

s), that are characterized by an unusual lifecycle that involves one or several generations of free-living adult worms. Human infection,

strongyloidiasis Strongyloidiasis is a human parasitic disease caused by the nematode called '' Strongyloides stercoralis'', or sometimes the closely related ''S. fülleborni''. These helminths belong to a group of nematodes called roundworms. These intestinal ...

, is caused by * ''

Strongyloides stercoralis ''Strongyloides stercoralis'' is a human pathogenic parasitic roundworm causing the disease strongyloidiasis. Its common name in the US is threadworm. In the UK and Australia, however, the term ''threadworm'' can also refer to nematodes of t ...

'', widespread in all tropical regions * '' Strongyloides fuelleborni'', a parasite of

primate Primates is an order (biology), order of mammals, which is further divided into the Strepsirrhini, strepsirrhines, which include lemurs, galagos, and Lorisidae, lorisids; and the Haplorhini, haplorhines, which include Tarsiiformes, tarsiers a ...

s in

Africa Africa is the world's second-largest and second-most populous continent after Asia. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 20% of Earth's land area and 6% of its total surfac ...

n and

Asia Asia ( , ) is the largest continent in the world by both land area and population. It covers an area of more than 44 million square kilometres, about 30% of Earth's total land area and 8% of Earth's total surface area. The continent, which ...

n tropics and of

human Humans (''Homo sapiens'') or modern humans are the most common and widespread species of primate, and the last surviving species of the genus ''Homo''. They are Hominidae, great apes characterized by their Prehistory of nakedness and clothing ...

s in

n tropics and

New Guinea New Guinea (; Hiri Motu: ''Niu Gini''; , fossilized , also known as Papua or historically ) is the List of islands by area, world's second-largest island, with an area of . Located in Melanesia in the southwestern Pacific Ocean, the island is ...

* '' Strongyloides papillosus,'' found in

cattle Cattle (''Bos taurus'') are large, domesticated, bovid ungulates widely kept as livestock. They are prominent modern members of the subfamily Bovinae and the most widespread species of the genus '' Bos''. Mature female cattle are calle ...

pig The pig (''Sus domesticus''), also called swine (: swine) or hog, is an omnivorous, domesticated, even-toed, hoofed mammal. It is named the domestic pig when distinguishing it from other members of the genus '' Sus''. Some authorities cons ...

sheep Sheep (: sheep) or domestic sheep (''Ovis aries'') are a domesticated, ruminant mammal typically kept as livestock. Although the term ''sheep'' can apply to other species in the genus '' Ovis'', in everyday usage it almost always refers to d ...

goat The goat or domestic goat (''Capra hircus'') is a species of Caprinae, goat-antelope that is mostly kept as livestock. It was domesticated from the wild goat (''C. aegagrus'') of Southwest Asia and Eastern Europe. The goat is a member of the ...

rabbit Rabbits are small mammals in the family Leporidae (which also includes the hares), which is in the order Lagomorpha (which also includes pikas). They are familiar throughout the world as a small herbivore, a prey animal, a domesticated ...

s, and

rat Rats are various medium-sized, long-tailed rodents. Species of rats are found throughout the order Rodentia, but stereotypical rats are found in the genus ''Rattus''. Other rat genera include '' Neotoma'' (pack rats), '' Bandicota'' (bandicoo ...

s * '' Strongyloides ransomi,'' found in

s * '' Strongyloides ratti'', found in

s *'' Strongyloides myopotami'', found in

coypu The nutria () or coypu () (''Myocastor coypus'') is a herbivore, herbivorous, semiaquatic rodent from South America. Classified for a long time as the only member of the family Myocastoridae, ''Myocastor'' has since been included within Echimy ...

(nutria), causes

dermatitis Dermatitis is a term used for different types of skin inflammation, typically characterized by itchiness, redness and a rash. In cases of short duration, there may be small blisters, while in long-term cases the skin may become thickened ...

similar to

. The condition is also called nutria itch. Treatment for strongyloides infection is

ivermectin Ivermectin is an antiparasitic drug. After its discovery in 1975, its first uses were in veterinary medicine to prevent and treat heartworm and acariasis. Approved for human use in 1987, it is used to treat infestations including head lice ...

thiabendazole Tiabendazole (International Nonproprietary Name, INN, British Approved Name, BAN), also known as thiabendazole (Australian Approved Name, AAN, United States Adopted Name, USAN) or TBZ and the trade names Mintezol, Tresaderm, and Arbotect, is a pr ...

References

{{Taxonbar, from=Q5267405 Parasitic nematodes of mammals Rhabditida genera Strongylidae