Prevalência de triatomíneos (Hemíptera: Reduviidae: Triatominae) infectados por Trypanosoma cruzi: sazonalidade e distribuição na região Ciénega do Estado de Jalisco, México

Abstract

A doença de Chagas, também conhecida como tripanossomíase americana é considerada um problema de saúde pública em 17 países latino-americanos. Cerca de 10 a 12 milhões de pessoas estão infectadas com o Trypanosoma cruzi, sendo esta uma das principais doenças transmitidas por insetos triatomíneos, na América Latina e endêmica em vários estados do México 7 24 . ABSTRACTThe physical and geographical characteristics of the Ciénega region, Jalisco, Mexico make it suitable for transmission of Trypanosoma cruzi, the causative agent for Chagas disease. This study characterizes the prevalence of triatomines infected by this parasite, their seasonality and their distribution in this region. A total of 328 triatomines were evaluated between January 2005 and June 2007, from 13 municipalities in the region. April, May and June were the months with the highest capture levels. Among the triatomines examined, 57.3% were positive for Trypanosoma cruzi, corresponding to 15.4% in urban areas and 84.6% in rural areas. The species with greatest prevalence was Triatoma longipennis and the species with the highest parasitism rate was Triatoma barberi, with an infection rate of 83.3%, whereas the rate for Triatoma longipennis was 67.5% (p<0.05). This natural infection in the captured vectors may indicate that individuals in this region have high exposure to Trypanosoma cruzi. The recent findings of positive Triatoma dimidiata in this region suggest that new species are becoming adapted to the ecological conditions of these populations.

An entomoepidemiological investigation of Chagas disease in the state of Ceará, Northeast Region of Brazil

“…These results are corroborated by other studies that reported higher infection rates and colonization during the dry season 13,14,15 . This disparity highlights the need for further longitudinal studies to define optimum timing for vector control insecticide application.…”

Molecular characterization of Trypanosoma cruzi Mexican strains and their behavior in the mouse experimental model

“…Control programs for Chagas disease and its vector have only recently been implemented in this country, whereas such programs have been already established in South American countries for several years 3,32 . The high rates of infection of triatomines observed in the State of Jalisco suggest an increased exposure of people living in this region to T. cruzi [33][34][35] . This fact has raised our interest to biologically and genetically characterize the strains circulating in this state.…”

Vigilancia de la presencia de triatominos mediante gallineros en el sur de Jalisco, México

“…Aparentemente, la dispersión de estas especies está relacionada con la conjunción entre el incremento en las temperaturas ambientales y la falta de lluvias, lo que favorece su movilidad, en búsqueda de alimento y un microambiente favorable para instalarse (13,14). Los porcentajes, tanto de M. longipennis como de T. barberi positivos para T. cruzi, fueron similares a lo reportado para estas especies en áreas geográficas cercanas a la de estudio, en el estado de Jalisco (ambas especies) y en los vecinos estado de Nayarit y Colima (M. longipennis) (6,8,14).…”

“…Por otra parte, si bien Triatoma barberi (Usinger, 1939) se considera un vector secundario en el área (7,(10)(11)(12), sus altos porcentajes de infección por T. cruzi (13,14) lo hacen un vector merecedor de vigilancia.…”