Paracoccidioidin and histoplasmin sensitivity in Tupí-Mondé Amerindian populations from Brazilian Amazonia

A cross-sectional epidemiological survey for paracoccidioidomycosis and histoplasmosis, including skin tests with paracoccidioidin and histoplasmin, physical examinations and X-rays, was conducted among three Tupí-Mondé Amerindian populations from Brazilian Amazonia. The study followed the diagnosis of an increasing number of cases of paracoccidioidomycosis among the Suruí in recent years. Positivity rates to paracoccidioidin and histoplasmin (> or = 5 mm of intradermal induration 24-48 h post-injection) were 43.8% and 78.7% for the Suruí, 6.4% and 5.8% for the Gavião and 14.9% and 80.5% for the Zoró, respectively. There was no significant difference in the results for males and females but marked differences were noted across age groups. The results of the univariate analysis were confirmed after adjustment for confounding variables by multiple logistic regression analysis: paracoccidioidin positivity was relatively high in the Suruí and histoplasmin positivity was relatively high in the Suruí and Zoró. The Suruí's greater exposure to Paracoccidioides brasiliensis, the causative agent of paracoccidioidomycosis, is probably associated with their adoption of new subsistence practices. The epidemiology of this mycosis among the Tupí-Mondé appears to be related to the environmental and socio-economic changes taking place in Amazonia.