Identification of blood-feeding sources in Panstrongylus, Psammolestes, Rhodnius and Triatoma using amplicon-based next-generation sequencing

Abstract

Background Triatomines are hematophagous insects that play an important role as vectors of Trypanosoma cruzi , the causative agent of Chagas disease. These insects have adapted to multiple blood-feeding sources that can affect relevant aspects of their life-cycle and interactions, thereby influencing parasitic transmission dynamics. We conducted a characterization of the feeding sources of individuals from the primary circulating triatomine genera in Colombia using amplicon-based next-generation sequencing (NGS). Methods We used 42 triatomines collected in different departments of Colombia. DNA was extracted from the gut. The presence of T. cruzi was identified using real-time PCR, and discrete typing units (DTUs) were determined by conventional PCR. For blood-feeding source identification, PCR products of the vertebrate 12S rRNA gene were obtained and sequenced by next-generation sequencing (NGS). Blood-meal sources were inferred using blastn against a curated reference dataset containing the 12S rRNA sequences belonging to vertebrates with a distribution in South America that represent a potential feeding source for triatomine bugs. Mean and median comparison tests were performed to evaluate differences in triatomine blood-feeding sources, infection state, and geographical regions. Lastly, the inverse Simpsonʼs diversity index was calculated. Results The overall frequency of T. cruzi infection was 83.3%. TcI was found as the most predominant DTU (65.7%). A total of 67 feeding sources were detected from the analyses of approximately 7 million reads. The predominant feeding source found was Homo sapiens (76.8%), followed by birds (10.5%), artiodactyls (4.4%), and non-human primates (3.9%). There were differences among numerous feeding sources of triatomines of different species. The diversity of feeding sources also differed depending on the presence of T. cruzi . Conclusions To the best of our knowledge, this is the first study to employ amplicon-based NGS of the 12S rRNA gene to depict blood-feeding sources of multiple triatomine species collected in different regions of Colombia. Our findings report a striking read diversity that has not been reported previously. This is a powerful approach to unravel transmission dynamics at microgeographical levels.

Diversity and Epidemiology of Bat Trypanosomes: A One Health Perspective

“…In agreement with this, a recent study in Colombia conducted an amplicon-based NGS characterization of Triatominae feeding sources (i.e., Panstrongylus, Rhodnius and Triatoma), and found multiple domestic and sylvatic vertebrate feeding sources (including chiropterans) per triatomine [183]. Another study obtained experimental evidence that R. prolixus can feed upon Carollia, Glossophaga, and Desmodus bats, suggesting that frequent transmission of T. cruzi between bats and humans via triatomine vectors is feasible [183,184]. Moreover, many bat species have omnivorous feeding habits and can feed on small mammals and triatomines, which means the probability of infection with T. cruzi could be slightly higher for these animals [183].…”

“…Although experimental trials have shown that some triatomine species can have strong preferences for a particular host when given a choice [ 180 , 182 ], subsequent studies have supported a scenario where T. cruzi vectors have adapted to multiple blood-feeding sources, which facilitates its transmission within and between sylvatic and domestic cycles [ 176 , 183 ]. In agreement with this, a recent study in Colombia conducted an amplicon-based NGS characterization of Triatominae feeding sources (i.e., Panstrongylus , Rhodnius and Triatoma ), and found multiple domestic and sylvatic vertebrate feeding sources (including chiropterans) per triatomine [ 183 ]. Another study obtained experimental evidence that R. prolixus can feed upon Carollia , Glossophaga , and Desmodus bats, suggesting that frequent transmission of T. cruzi between bats and humans via triatomine vectors is feasible [ 183 , 184 ].…”

“…Another study obtained experimental evidence that R. prolixus can feed upon Carollia , Glossophaga , and Desmodus bats, suggesting that frequent transmission of T. cruzi between bats and humans via triatomine vectors is feasible [ 183 , 184 ]. Moreover, many bat species have omnivorous feeding habits and can feed on small mammals and triatomines, which means the probability of infection with T. cruzi could be slightly higher for these animals [ 183 ].…”

Identification of Multiple Blastocystis Subtypes in Domestic Animals From Colombia Using Amplicon-Based Next Generation Sequencing

“…Because in samples from feces mixed infections are common ( 8 , 83 , 84 ), it is important to deploy NGS tools in studies of Blastocystis subtype diversity to have a better picture of STs present within a host. The usefulness of NGS in detecting mixed infections has also been demonstrated in other organisms such as Trypanosoma cruzi and Trypanosoma rangeli where NGS successfully detected co-infections of these two parasites in infected triatomines ( 85 ) and in triatomine food sources ( 86 ). NGS has aided in the determination of the diversity of low-density Plasmodium falciparum infections ( 87 ).…”

Host Bloodmeal Identification in Cave-Dwelling Ornithodoros turicata Dugès (Ixodida: Argasidae), Texas, USA

“…This method of metabarcoding and deep sequencing would be advantageous given soft tick biology, including multiple bloodmeals obtained during immature development and multiple gonotropic cycles of adults. The amplicon deep sequencing approach would allow the ID of not just the most recent bloodmeal but also the potential to detect prior vertebrate bloodmeals ( 49 , 50 ).…”