Geographic Distribution of Chagas Disease Vectors in Brazil Based on Ecological Niche Modeling

Abstract

Although Brazil was declared free from Chagas disease transmission by the domestic vectorTriatoma infestans, human acute cases are still being registered based on transmission by native triatomine species. For a better understanding of transmission risk, the geographic distribution of Brazilian triatomines was analyzed. Sixteen out of 62 Brazilian species that both occur in>20 municipalities and present synanthropic tendencies were modeled based on their ecological niches.Panstrongylus geniculatusandP. megistusshowed broad ecological ranges, but most of the species sort out by the biome in which they are distributed:Rhodnius pictipesandR. robustusin the Amazon;R. neglectus,Triatoma sordida, andT. costalimaiin the Cerrado;R. nasutus,P. lutzi,T. brasiliensis,T. pseudomaculata,T. melanocephala, andT. petrocchiaein the Caatinga;T. rubrovariain the southern pampas;T. tibiamaculataandT. vitticepsin the Atlantic Forest. Although most occurrences were recorded in open areas (Cerrado and Caatinga), our results show that all environmental conditions in the country are favorable to one or more of the species analyzed, such that almost nowhere is Chagas transmission risk negligible.