Animal Models of Trypanosoma cruzi Congenital Transmission

Chagas disease, initiated by the etiological agent Trypanosoma cruzi, is an endemic infection in the American continent. Although vectorial transmission of T. cruzi is recognized as the main mode of infection, other routes such as congenital and blood transfusion are also documented as important methods of transmission. T. cruzi maternal-fetal transmission has been recorded in humans and examined by some investigators in naturally and experimentally infected mammals. Dogs are recognized as the major reservoir host in maintaining the domestic transmission of T. cruzi; however, the importance of congenital transmission in preserving the infection cycle in dogs has not been studied in detail. In this article, we reviewed the current knowledge of congenital transmission of T. cruzi in humans and compared the placental architecture of humans and different animals with particular attention to rodents, dogs, and non-human primates that have been used as experimental models of T. cruzi infection, congenital transmission, and Chagas disease pathogenesis. The placentas of humans and animals have some similar and dissimilar characteristics that should inform the study design and interpretation of results when evaluating the efficacy of new anti-parasite drugs and therapies against congenital infection.