Geohelminths: public health significance.

The worldwide prevalence of geohelminths and their unique place in evolutionary biology have attracted research focus. These major soil-transmitted intestinal nematodes that cause human diseases are the nematode roundworm (Ascaris lumbricoides), the whipworm (Trichuris trichiura) and the two hookworms (Ancylostoma duodenale and Necator americanus), often collectively referred as geohelminths. Studies of geohelminthiasis in poorly nourished children in developing regions report that geohelminths contribute to stunted growth and cognitive impairment. Insights into immunology have shed light on the modulatory role of the parasite on the host immune system and have defined the role of T cells in controlling geohelminthic infection. Recent molecular biological techniques have created an opportunity to analyse the interaction between parasites and their hosts at the molecular level. This paper is a review of the recent literature that examined the prevalence of geohelminthiasis in developing countries, the association between geohelminths in relation to public health, parasitological/diagnostic features, and therapeutic and preventive aspects of these major soil-transmitted helminth (STH) pathogens in humans.