EPIDEMIOLOGY OF HUMAN HOOKWORM AND ASCARIS-LUMBRICOIDES INFESTATIONS IN RURAL GAMBIA

In a cross-sectional study of helminth infections in a rural village i n The Gambia, West Africa, hookworm, probably Necator americanus and A scaris lumbricoides were found to be the most prevalent helminths pres ent at prevalence levels of 30% and 25% respectively. Other parasites present were Trichuris trichiura (2.4%) and Schistosoma mansoni (1.5%) . The mean egg counts of N. americanus and A. lumbricoides in all age groups and in the total population were low. Egg counts between age an d sex groups were not statistically significant. The frequency distrib utions of both N. americanus and A. lumbricoides were overdispersed wi th the majority of the sample population producing none or few eggs, a nd a small minority producing relatively large amounts of eggs. Large variance: mean ratios within age groups and the total study population suggested a high degree of aggregation of the parasites in this commu nity.