AUTHOR=Mann Allison E. , Mitchell Elizabeth A. , Zhang Yan , Curtis-Robles Rachel , Thapa Santosh , Hamer Sarah A. , Allen Michael S. 

TITLE=Comparison of the Bacterial Gut Microbiome of North American Triatoma spp. With and Without Trypanosoma cruzi

JOURNAL=Frontiers in Microbiology

VOLUME=11

YEAR=2020

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2020.00364

DOI=10.3389/fmicb.2020.00364

ISSN=1664-302X

ABSTRACT=<p>Chagas disease, caused by the hemoflagellate protist <italic>Trypanosoma cruzi</italic>, affects nearly 6 million people worldwide, mainly in Latin America. Hematophagous triatomine insects (“kissing bugs”) are the primary vectors of <italic>T. cruzi</italic> throughout the Americas and feed on a variety of animals, including humans. Control of triatomines is central to the control of <italic>T. cruzi</italic> infection. Recent advances in mitigation of other insect-borne diseases via the manipulation of insect-associated bacteria as a way to halt or slow disease transmission has opened questions to the applicability of these methods to Chagas disease vectors. Few studies have examined the hindgut microbiome of triatomines found in North America. In the current study, two species of triatomines were collected across Texas, United States, screened for the presence of <italic>T. cruzi</italic>, and analyzed for the bacterial composition of their hindguts using a 16S rRNA gene-fragment metabarcoding approach. We compared diversity of microbial community profiles across 74 triatomine insects to address the hypothesis that the richness and abundance of bacterial groups differ by <italic>T. cruzi</italic> infection and strain type, blood meal engorgement status, insect species, sex, and collection location. The gut microbial community of individual triatomines was characterized by low intraindividual taxonomic diversity and high interindividual variation that was weakly predicted by triatomine species, and was not predicted by triatomine sex, collection location, <italic>T. cruzi</italic> infection status, or blood meal score. However, we did find bacterial groups enriched in <italic>T. cruzi</italic>-positive individuals, including Enterobacterales, and <italic>Petrimonas</italic>. Additionally, we detected <italic>Salmonella enterica</italic> subspecies <italic>diarizonae</italic> in three triatomine individuals; this species is commonly associated with reptiles and domesticated animals and is a pathogen of humans. These data suggest that <italic>Triatoma</italic> spp. in Texas have variable patterns of colonized and transient bacteria, and may aid in development of novel means to interfere with transmission of the Chagas disease parasite <italic>T. cruzi</italic>. Deeper understanding of the effects of parasite infection on diverse insect vector microbiomes may highlight disease transmission risk and facilitate discovery of possible intervention strategies for biological control of this emerging vector-borne disease of global health significance.</p>