Risk factors for human schistosomiasis in the Upper Benue valley, in northern Cameroon.

The Upper Benue valley is inhabited by human populations of mixed background and socio-economic status. The area is an old and intense focus of both urinary schistosomiasis (caused by Schistosoma haematobium) and intestinal schistosomiasis (caused by S. mansoni). Most of the local villages have stand-pipes that provide clean drinking water but bathing, laundry, dishwashing and swimming are largely confined to nearby, snail-infested rivers, streams, irrigation canals and pools. The results of interviews and a multivariate analysis indicated that, in this region of Cameroon, a subject's age, knowledge of schistosomiasis, ethnic group and intensity of water contact (with rivers, streams and pools) were all significantly associated with schistosome infection. Curiously, a high level of knowledge about schistosomiasis was positively associated with infection.