Trypanosoma cruzi-infected triatomines and rodents co-occur in a coastal island of northern Chile

Abstract

Trypanosoma cruzi, the cause agent of Chagas disease, is transmitted mainly by blood-feeding insects of the subfamily Triatominae. The T. cruzi life cycle alternates between triatomines and mammalian hosts, excluding birds and reptiles. Triatomines of Mepraia genus are wild vectors of T. cruzi in Chile. Mepraia specimens infected with T. cruzi have been detected in Pan de Azúcar and Santa María islands. The most common vertebrates that inhabit these islands are birds and reptiles, and it is unknown whether small mammals are present. Consequently, it is relevant to know whether there are any T. cruzi-infected small mammals on those islands to elucidate the T. cruzi cycle. To clarify this crossroads, islands of northern Chile were explored to determine if T. cruzi-infected triatomines and rodents co-occur in islands of northern Chile. T. cruzi DNA was detected by conventional and real-time PCR in three islands: on Santa María and Pan de Azúcar islands T. cruzi was detected in Mepraia sp samples, while on Pan de Azúcar (6.1%) and Damas islands (15%) was detected in the rodent Abrothrix olivacea. We show for the first time in Chile the occurrence of insular rodents infected with T. cruzi, and a complete T. cruzi life cycle in a coastal island. Our results provide new insights to understand the T. cruzi infection in the wild cycle.

Over-dispersed Trypanosoma cruzi parasite load in sylvatic and domestic mammals and humans from northeastern Argentina

“…The few published studies that have evaluated T. cruzi parasitemia in sylvatic hosts mainly focused on synanthropic and wild rodent species from Chile and Mexico, which showed a median parasite load between 1.0 and 6.2 Pe/ml [ 23 , 24 , 26 , 58 ] In one study, T. cruzi- infected marsupials, such as Didelphis marsupialis (Didelphimorphia, Didelphidae) and Marmosa murina (Didelphimorphia, Didelphidae), from Colombia were qPCR-positive, with a median parasite load of 27.4 and 0.2 Pe/ml, respectively [ 25 ]. In our study, the parasite load of D. albiventris from two regions of northern Argentina that differed in the intensity of T. cruzi transmission was not significantly different.…”

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

“…For mainland samples, the presence of T. cruzi DNA and IAC was detected by real-time PCR using reported protocols [18]. We used a previously reported infection frequency of island kissing bugs detected by real-time PCR [13].…”

“…A serological study showed that, on Pan de Azúcar Island (26 • S), M. parapatrica fed on marine birds (78%), sea mammals (15%), and reptiles (7%) [12]. In the same island T. cruzi-infected rodents (6.1% infection frequency) and triatomine bugs (20.3% infection frequency) have been reported [13]. Other studies have reported M. gajardoi populations associated with fishers' dwellings and T. cruzi infection in dogs living nearby, warning about the epidemiological risk of these triatomine bugs due to the proximity of kissing bugs to human settlements, dogs acting as a reservoir and the potential invasion of triatomine bugs in fishers' coves [14,15].…”

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

“…from now on), which inhabits between the distributions of M. parapatrica and M. gajardoi (23°25′ to 23°28′ S) [ 9 ]. The coastal species inhabit landscapes with low vegetation under stones and in rock crevices, associated with marine bird nests, rodent burrows and lizards [ 9 , 10 ]. Although each of the Mepraia species forms well-supported clades, the phylogenetic relationships between these lineages are still unresolved, leading to controversy regarding the colonization routes of Mepraia species in Chile [ 7 , 9 ].…”