Geohelminth

Geohelminths are soil-transmitted parasitic nematodes with a life cycle that involves no intermediate hosts or vectors: they infect many animals, including humans, and are spread by the faecal contamination of soil, foods and water. Most species have juvenile forms which move around the body of the host, but all species inhabit the intestine in their adult stages and release their eggs in the host's faeces. The diseases they cause can thus be local or systemic.

Four species cause widespread disease in humans: "Ascaris lumbricoides" (the large roundworm, which causes ascariasis), "Trichuris trichiura" (the whipworm, which causes trichuriasis), and the blood-feeding hookworms "Ancylostoma duodenale" and "Necator americanus", which cause ankylostomiasis.

Geohelminth infection is a major health problem of children from rural areas of developing countries like India. It is an important cause of morbidity in school age children who harbour the highest intensity of worm infestation. Some of the significant morbidity attributed to intestinal helminthiasis is malnutrition, growth retardation, anemia, vitamin A deficiency and impaired intellectual performance. Thus, hookworm poses a serious threat to developing countries trying to raise their level of education.