Soil-transmitted helminthiases (STH) are a group of
intestinal nematode infections caused by Ascaris
lumbricoides (roundworms), Trichuris trichiura (whipworms),
Necator americanus and Ancylostoma duodenale
(hookworms). These parasitic infections adversely
affect nutritional status and impair cognitive processes.
The public health intervention recommended by WHO
for the control of morbidity associated with STH is the
periodic administration of the anthelmintic medicines
(albendazole or mebendazole) in areas where prevalence
of any STH infection equals or exceeds 20%.