Control of schistosomiasis mansoni in Ravena (Sabara, State of Minas Gerais, Brazil) through water supply and quadrennial treatments

ABSTRACT

In this study, the results obtained in a control programme of schistosomiasis in Ravena (Sabara, Minas Gerais) between 1980 and 1992 are evaluated. Control measures used in this programme were specific treatment of people infected with Schistosoma mansoni at four years-intervals (1980/84/88) and the supply of tap water to 90 per cent of the residences in 1980. A significant reduction of the prevalence (36.7 per cent to 11.5 per cent, pó 0.05) and of the intensity of the infection (228.9 eggs per gram of feces (eps), s=3.7 to 60.3 epg, s= 3.5, pó 0.05) was observed. No cases of the severe form of the disease were diagnosed in the area. Factors independently associated with the infection were in 1980 daily sand extration and the lack of tap water in residences and in 1992 daily sand extration and fishing and weekly swimming. Concluding, the supply of tap water together with quadrennial treatment significantly diminished both the prevalence and intensity of the S. mansoni infection, with the additional gain of persistent low indices even after four-year intervals between the treatments.