Ascaris lumbricoides is the "large roundworm" of humans, growing to a length of up to 35 cm (14 in). It is one of several species of Ascaris. An ascarid nematode of the phylum Nematoda, it is the most common parasitic worm in humans. This organism is responsible for the disease ascariasis, a type of helminthiasis and one of the group of neglected tropical diseases. An estimated one-sixth of the human population is at some point infected by A. lumbricoides or another roundworm. Ascariasis is prevalent worldwide, especially in tropical and subtropical countries.
|An adult female Ascaris worm|
It has been proposed that Ascaris lumbricoides and Ascaris suum (pig roundworm) are the same species.