Blood-Meal Sources and Trypanosoma cruzi Infection in Coastal and Insular Triatomine Bugs from the Atacama Desert of Chile

Abstract

Mepraia parapatrica is one of the lesser known and less abundant sylvatic triatomine species naturally infected by the protozoan Trypanosoma cruzi, the etiological agent of Chagas disease. M. parapatrica lives in sympatry with T. cruzi-infected rodents, but only birds, reptiles, and marine mammals have been reported as blood-meal sources of this vector species by serology. The distribution range of this kissing bug overlaps with fishers’ settlements and tourist areas, and therefore the study of the blood-meal sources of this triatomine species is relevant. Here, we determined the blood-meal sources of M. parapatrica by NGS or standard sequencing from a coastal mainland area and an island in northern Chile, and T. cruzi infection by real-time PCR. The blood-meals of. M parapatrica included 61.3% reptiles, 35.5% mammals (including humans) and 3.2% birds. Feeding on reptiles was more frequent on the mainland, while on the island feeding on mammals was more frequent. The presence of T. cruzi-infected triatomine bugs and humans as part of the diet of M. parapatrica in both areas represents an epidemiological threat and potential risk to the human population visiting or established in these areas. Currently there are no tools to control wild triatomines; these results highlight the potential risk of inhabiting these areas and the necessity of developing information campaigns for the community and surveillance actions.

Vector mapping and bloodmeal metabarcoding demonstrate risk of urban Chagas disease transmission in Caracas, Venezuela

“…This update also describes triatomine biting reports by MDC inhabitants and uses cytochrome b (cytb) metabarcoding to provide a snapshot of triatomine blood feeding patterns in the parishes with highest triatomine collection yield. Bloodmeal metabarcoding (most often targeting cytb and 12S) is widely used in the study of Chagas disease vector ecology [22][23][24][25][26][27][28][29][30]. For example, this tool has helped infer triatomine dispersal rates between wild and human-inhabited ecotopes (e.g., cases of high connectivity and re-infestation potential shown for T. infestans in Bolivia [22] and T. dimidiata in Ecuador [23]), or gauge triatomine diet specialization and overlap (e.g., within [24] and across triatomine species in Colombia [25]).…”

Testing Phylogeographic Hypotheses in Mepraia (Hemiptera: Reduviidae) Suggests a Complex Spatio-Temporal Colonization in the Coastal Atacama Desert

“…However, Mepraia are fully dependent on other animals to complete their biological cycle. Mepraia have opportunistic feeding behaviour, i.e., they mainly feed on the most abundant or available hosts, including mammals, lizards and birds [ 38 , 39 ]. Therefore, the phylogeographic patterns of Mepraia are not only affected by abiotic forces [ 37 ], but also depend on the status and distribution of the animal populations on which they feed.…”