Elucidating Trypanosoma Cruzi Reservoirs Across South and Central America: A Review of Over 70 Years of Sero-epidemiological Evidence

Abstract

Abstract Chagas disease, or American trypanosomiasis, is the most important neglected tropical disease in terms of Disability-Adjusted Life Years (DALYs) in the Americas. The disease is caused by infection with the protozoan parasite Trypanosma cruzi, which has an incredibly complex transmission cycle that can involve any one of 150 triatomine bug species in addition to more than a hundred mammalian species. Taking into consideration this complexity in combination with the gravity of Chagas disease, it is imperative to understand the vector-host relationships that are key to transmission cycles in a given region or habitat to prevent human infection. While much contemporary scholarship has been done with regards to triatomine vector ecology and domestic animal reservoir potential, the relationship between ecological disturbance and human transmission or the relevance of mammals to T. cruzi transmission and maintenance in the wild remain minute. Therefore, we aimed to: 1) briefly summarize the Chagas literature, 2) review and extract prevalence data from the literature on mammal species tested for T. cruzi infection in South and Central America and 3) discuss gaps in the literature as well as suggest further research. In this study, 112 articles published between 1940-2016 were reviewed, in which over 120 species were reported to have natural T. cruzi infection. Prevalence data from these articles were used to assess whether species identity is an indicator of infection. The ultimate purpose of this study is to highlight what is known with respect to T. cruzi transmission and wild mammals in order to better understand where to focus future studies.