Schistosomiasis in Swaziland--a comparative study of three irrigated estates

The prevalence of Schistosomiasis and the distribution of the snail intermediate hosts on three adjoining irrigated estates in the lowveld of Swaziland was investigated. The prevalence rates of Schistosoma haematobium and S. mansoni among estate employees was lower than anticipated and there was a marked difference between the prevalence rates of S. mansoni between estates. The reasons for this and the influence of water supplies and agricultural practice on the prevalence of schistosomiasis are discussed.