- The threadworm, a genus of small nematode parasites (superfamily Rhabditoidea), commonly found in the small intestine of mammals (particularly ruminants), that are characterized by an unusual life cycle that involves one or several generations of free-living adult worms. Human infection is chiefly by S. stercoralis, the small roundworm of man, widespread in all tropical regions, or by S. fuelleborni, a parasite of non-human primates in African and Asian tropics and of humans in African tropics. The subspecies S. fuelleborni kellyi occurs in New Guinea where it causes widespread infection. Fatal infection in 2-month-old infants, possibly infected by transmammary transmission, produces the condition known locally as swollen belly disease or swollen belly syndrome, which causes grossly distended abdomens, invariably fatal in these infants. Other species include S. papillosus in cattle, sheep, and goats, and S. ransomi in swine. [G. strongylos, round, + eidos, resemblance]
* * *Stron·gy·loi·des .strän-jə-'lȯi-.dēz n a genus (the type of the family Strongyloididae) of nematode worms having both free-living males and females and parthenogenetic females parasitic in the intestine of various vertebrates and including some medically and economically important pests of humans
* * *n.a genus of small slender nematode worms that live as parasites inside the small intestines of mammals. S. stercoralis infects the human small intestine (see strongyloidiasis); its larvae, which are passed out in the stools, develop quickly into infective forms.
* * *Stron·gy·loi·des (stron″jə-loiґdēz) a genus of phasmid nematodes of the family Rhabditidae, widely distributed as intestinal parasites of mammals.
Medical dictionary. 2011.