Determinantes epidemiológicos da esquistossomose mansoni em Ravena-MG: análise uni e multivariada das condições sócio-econômicas e sanitárias, no período de 1977 a 1980

Abstract

The aim of the study has been to determine the prevalence, infection intensity, clinical forms, and risk groups and factors, recarding shistosomiasis in the Ravena district of Sabara, a town in the State ofMinas Gerais. The district is made up of three localities: Ravenópolis, Ravena e Lavapés, whose endemic prevalences were 20.1%. 42.6% and 63.9% respectively. ln a comparison of the three localities, only the 25 to 29 years age group did not present a significant prevalence difference, and the individuals aged 10-14 and 20-29 were the ones who showeddifferences between geometric averages of the number os Schistosoma mansoni eggs. The prevalence in the district was statistically greater in the men. The hepatointestinal form had been associated with age; under fifteens presented a risk B.B5 times greater than that of adults. The univariate analisys of the risk factors showed an association of the infection with individuals of the male sex (odds ratio 1.7): to daily.weekly and fortnightly contacts with natural water (DR respectively 3.5; 3.7 and 3.5l to the sources of the water used in the home for drinking, washing domestic utensils, washing clothes and having baths (ORrespectively 2.5; 2.5 and 2.8); and to the extraction of sand from the rivers (DR=iO.4l. By means of the multivariate analysis. it was concluded that Lavapes was the locality independently associated with the S.mansoni infection, and where the greatest risks of infection were due to unsuitable water sources and sanitation as compared with those at Ravens andRavenópolis. The solution to these problems in Lavapes would have a great impact on reducing shistosomiasis in the district.