[Schistosomiasis--infection and race of carriers]

The geometric average (parasitical charge) of the eggs of Schistosoma mansoni quantified by Kato-Katz method in five parasitological fecal exams of 868 individuals, was correlated to sex, age and racial groups. The higher averages were observed in females from 6 to 15 years old and in black individuals--the analysis of variation showed, however, more significant effect of age and of sex. However, when the average results were translated, qualitatively into positives and negatives no sexual differences were observed and only the individuals under 5 years old were significantly more negative than those over 6 years old. Nevertheless, in these age brackets the white individuals were mostly negative, and in the sample group they reach statistic significance (X2(2) = 20.76 p 0.0001)--with the following percentage of negatives: whites--26.8%; mulatos--16.3% and negroes--9.1%. These results reinforce the hypothesis, among other predisponent factors of Schistosomiasis--infection, of the effect of the social-economical level in the Brazilian black population.