Transmission dynamics of Schistosoma mansoni in an irrigation setting in Ethiopia

Abstract

Summary: The transmission dynamics of S. mansoni was studied in the Metehara Sugar Estate for 12 months. The prevalence of human infection ranged from 7.4% to 71.3% for 6 villages in the Estate. The infection rate was highest in the 10-14 years of age while the intensity reached peak in the 5-9 years. There were significant variations in the focality and seasonality of transmission. Biomphalaria pfeifferi which was persistent year round, was most abundant during the dry season. Absence of potable water supply and sanitary facilities, proximity to irrigation canals, and overcrowding are some of the most important factors influencing transmission of schistosomiasis in Metehara Sugar Estate. Mass chemotherapy and mollusciciding should be launched in Awash and Chore farm villages to control transmission, while treatment of children under 15 years is believed to control morbidity in other villages. [Ethiop. J. Health Dev. 1995 9(3): 146-158]