Ataques de populaçöes humanas por triatomíneos silvestres na Amazonas: uma nova forma de transmissäo da infecçäo chagásica? / Human populations attacked by wild Triatominae in the Amazonas: a new form of transmission of Chagas disease?

Comprovou-se o "ataque" de triatomíneos silvestres (Rhodnius brethesi) a colhedores de piaçaba (Leopoldinia piaçaba), em piaçabal na localidade de Acuquaia, no Rio Padauari, afluente do Rio Negro, no Município de Barcelos, Estado do Amazonas, onde em trabalho anterior verificamos uma prevalência sorológica para anticorpos anti-T. cruzi em 12,5 por cento da populaçao na sede do município, com uma forte associaçao do contato dessa populaçao com triatomíneos silvestres, conhecidos na área como "piolho da piaçava", os quais vivem predominantemente nas piaçabeiras. O "ataque"de triatomíneos a populaçoes humanas foi possivelmente o mecanismo inicial de abordagem dos triatomíneos ao homem, adaptando-se posteriormente ao seu peridomicílio e domicílio, principalmente em áreas desmatadas ou de cerrado com poucos reservatórios silvestres. No caso do Amazonas, relatado neste trabalho, os triatomíneos estavam provavelmente famintos por escassez de outros animais de sangue quente para sua alimentaçao.

Encuesta epidemiologica de histoplasmosis, paracoccidioidomicosis y leishmaniasis mediante pruebas cutaneas / Epidemiological survey of histoplasmosis, paracoccidioidomycosis, and leishmaniasis based on skin tests

In a village in Brazil's Amazonian jungle, skin test with histoplasmin, paracoccidioidin, and leishmanin were given to a group of 400 subjects aged 10 and older, of both sexes, who also responded to a questionnaire on their history of infectious diseases, There was a high prevalence of positive results in the three tests. The pattern of the results supports the hypothesis that testing with two mycotic antigens does not produce cross-reactions in asymptomatic subjects and that the sources of exposure to the fungi are probably independent. The positive reaction to leishmanin in males was related to farming activities, hunting, fishing, and the collection of firewood; the reactions in females showed a limited correlation with fishing and a much stronger one with the collection of firewood. With the mycotic antigens, the positive reactions were no associated with any of these activities. There was a high correlation of results using a leishmanin obtained from Leishmania Mexicana amazonensis and a combined leishmanin obtained from Leishmania mexicana and Leishmania brasiliensis. The diameter of induration was generally larger for the latter of these antigens, which induced some very intense responses. The frequency distribution of the magnitude of reaction was heterogeneous in subjects with positive reactions to both leishmanin and paracoccidioidin. Evidence that these findings are consistent with