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Background: Chagas disease is a zoonotic disease caused by the protozoan parasite Trypanosoma cruzi. The role of dogs as sentinels has been proposed in multiple regions, as they are a domestic reservoir for T. cruzi. Our objective was to determine the prevalence of T. cruzi infection in shelter dogs from southern Louisiana, and assess its magnitude and distribution. Results: A total of 540 dogs were enrolled, from 20 animal shelters, and tested for T. cruzi infection by serological tests (rapid test, ELISA and western blot) and PCR. We documented a high prevalence of T. cruzi infection with at least 6.9% (95% CI: 5.0–9.3%) seropositive and 15.7% (95% CI: 12.9–19.1%) PCR-positive dogs. Serological tests showed limited agreement, and concordance between serology and PCR was higher when considering reactivity to single serological tests. Trypanosoma cruzi infection was distributed evenly among shelters. Infection was significantly correlated with age (R2 = 0.99), indicating an incidence of new cases of 2.27 ± 0.25% per year. Conclusion: Trypanosoma cruzi infection is a significant and widespread veterinary problem in shelter dogs in the region, although it is mostly unnoticed by health professionals. This highlights the need for greater awareness of T. cruzi infection among the veterinary community and dog owners. [ABSTRACT FROM AUTHOR]

Background Trypanosoma cruzi is a zoonotic pathogen of increasing relevance in the USA, with a growing number of autochthonous cases identified in recent years. The identification of parasite genotypes is key to understanding transmission cycles and their dynamics and consequently human infection. Natural T. cruzi infection is present in captive nonhuman primate colonies in the southern USA. Methods We investigated T. cruzi genetic diversity through a metabarcoding and next-generation sequencing approach of the mini-exon gene to characterize the parasite genotypes circulating in nonhuman primates in southern Louisiana. Results We confirmed the presence of T. cruzi in multiple tissues of 12 seropositive animals, including heart, liver, spleen and gut. The TcI discrete typing unit (DTU) predominated in these hosts, and specifically TcIa, but we also detected two cases of coinfections with TcVI and TcIV parasites, unambiguously confirming the circulation of TcVI in the USA. Multiple mini-exon haplotypes were identified in each host, ranging from 6 to 11. Conclusions The observation of multiple T. cruzi sequence haplotypes in each nonhuman primate indicates possible multiclonal infections. These data suggest the participation of these nonhuman primates in local parasite transmission cycles and highlight the value of these naturally infected animals for the study of human Chagas disease. [ABSTRACT FROM AUTHOR]

The article discusses issues related to emergence of Neglected tropical diseases (NTDs) in the U.S. According to an estimate all of the "bottom 100 million" in the nation suffer from at least one NTD including Chagas disease. It has been stated that there are many similarities between people living with Chagas disease and people living with HIV/AIDS that includes requirement for prolonged treatment courses in both diseases.

Background/purpose: The parasitic protozoa Trypanosoma cruzi, is widely distributed throughout the Americas. We explored the nature of T. cruzi infection in small rodents from New Orleans (LA, USA), an enzootic region of the parasite in North America., Methods: We characterized the full complement of discrete typing units (DTUs) in rodent hosts through next-generation metabarcoding, as conventional PCR and Sanger sequencing approaches only detect the dominant genotype in biological samples. We assayed DTU diversity in tissue samples from 6 T. cruzi PCR positive rodents. The intergenic region of the mini-exon gene was amplified and sequenced on a MiSeq platform. A total of 141 sequences were aligned using Muscle, and TCS networks were constructed to identify DTUs in the samples., Results: We detected distinct and varying assemblages of DTUs in the rodent hosts. Highly diverse DTU assemblages were detected, with 6-32 haplotypes recovered per individual, spanning multiple DTUs (TcI,TcII, TcIV, TcV and TcVI). Haplotypes varied in frequencies from 82% to less than 0.1%. DTU composition varied according to the tissue analyzed. Rural and urban rodents carried similarly diverse DTU assemblages, though urban rodent species tended to harbor more haplotypes than their sylvatic counterparts., Conclusion: Our results affirm that mammalian hosts can concurrently harbor a diverse complement of parasites, and indicate that there is greater diversity of T. cruzi DTUs present in North America than previously thought. Further investigation is warranted to understand the role of commensal rodents as a reservoir for T. cruzi in sylvatic and peridomestic environments., (Copyright © 2019. Published by Elsevier B.V.)