Ecoepidemiologia da doença de chagas em uma região do estado da Bahia, Brasil

Abstract

SANTOS, F. Ecoepidemiology of Chagas disease in a region of the state of Bahia, Brazil. 2022. 96p. Tese (Doutora em Ciência Animal nos Trópicos) – Escola de Medicina Veterinária e Zootecnia – Universidade Federal da Bahia, 2022. This study aimed to characterize the vectorial role of triatomines found in the district of Santo Inácio, Bahia, Northeastern Brazil, and to estimate the frequency of infection by T. cruzi in these vectors, as well as in dogs, wild mammals and humans. Possible blood food sources of triatomine were analyzed. In addition, it assesses the perception, knowledge, and preventive practices adopted by the population about Chagas disease (CD). Residents sampled (n = 126) were seronegative for T. cruzi, while 17.5% (7/40) of the dogs sampled were seropositive. Of the wild mammals captured, one specimen of Didelphis albiventris (1/3) and another of Kerodon rupestris (1/5) were positive for T. cruzi by PCR. None Thrichomys sp. (0/23) was positive for T. cruzi. Of the 169 triatomines captured, the species Triatoma sherlocki was the most prevalent (n = 164), followed by the species Triatoma sordida (n = 4) and Panstrongylus sherlocki sn Panstrongylus lutzi (n = 1). The infection rate for T. cruzi by PCR in the triatomine species analyzed was 18.5% (28/151), 0% (0/3) and 100% (1/1), respectively. The detection of the food source was possible in 56 triatomines of the species T. sherlocki. The species K. rupestris was the most frequent food source (35.7%), followed by Gallus gallus (17.9%), D. albiventris (14.3%), Homo sapiens (14.3%), Tropidurus hispidus (7.1%), Leopardus geoffroyi (5.3%), Conepatus semistriatus (1.8%), Thrichomys inermis (1.8%) and Rattus norvegicus (1.8%). The residents have limited perception, and knowledge about CD, reflecting the low adoption of prevention and control practices for triatomines in their dwellings. The results suggest the existence of domestic, peridomestic and wild cycles of T. cruzi transmission, configuring a latent risk of infection for the human population.