Trypanosoma cruzi Genotypes in Mepraia gajardoi from Wild Ecotopes in Northern Chile

Abstract

Abstract. We evaluated Trypanosoma cruzi infection in 397 wild Mepraia gajardoi specimens from five coastal localities in northern Chile by detection of minicircle DNA by polymerase chain reaction. The wild capture sites were classified into two ecotopes: a fully wild ecotope (ecotope 1) and a wild ecotope near human dwellings (ecotope 2). Infection rates varied between 11% and 27%. Minicircle hybridization assays showed that T. cruzi lineages Tc II and Tc VI were commonly detected in ecotope 1 and ecotope 2, respectively. These results are discussed in the context of insect proximity to human dwellings, the alimentary profile of Mepraia sp., T. cruzi lineages detected in the past in the same diseaseendemic area circulating in humans, and Triatoma infestans.

An entomological and seroepidemiological study of the vectorial‐transmission risk of Chagas disease in the coast of northern Chile

“…() in the same sampled sections; although the differences in infection found by Toledo et al . () could be explained by the fact that most of our specimens collected in San Marcos were associated with birds, in which the parasite does not reproduce owing to the mechanism of natural resistance to the parasite (Kierszenbaum et al, ).…”

“…This value could be explained by the low prevalence of the parasite in the insect vectors found in this study (5.8%). Previous studies reported variables infection rates of M. gajardoi between 11 and 27% in different localities of Region XV and Region I (Carvajal et al ., ; Botto‐Mahan et al, ; Jercic et al ., ; Toledo et al ., ). These rates are lower than those found in M. spinolai .…”

“…Another possible explanation for the low infection of M. gajardoi with T. cruzi (5.8%), compared with other studies (11–27%), is that the most of the analysed specimens were nymphs (50/52), also indicated by Toledo et al . (). The results reported by Canals et al .…”

“…Mepraia gajardoi is a coastal species associated with nests of seabirds, caves of reptiles and wild rodents, and with an extremely arid climate with less than 2 mm of annual precipitation (Frías et al, 1998;Toledo et al, 2013). The presence of this species, on the northern coast of Chile, characterized by coastal desert climate, means that this insect may come into contact with people and their homes and may cause a particular epidemiological situation, differing from the situation that occurs in central to northern Chile with M. spinolai, which occasionally, as a result of immigration from peri-domestic or wild environments, colonizes human dwellings (Frías et al, 1995;Cattan et al, 2002).…”

New records of Mepraia (Hemiptera, Reduviidae, Triatominae) in Chile

“…Sagua et al () collected 95 specimens of M. spinolai, including adults and nymphs of all five instars in Pan de Azúcar, an island that lies between the regions of Antofagasta and Atacama in northern Chile. Toledo et al () collected 397 adults and nymphs of M. gajardoi at five locations in the coastal region of northern Chile. Campos et al () collected 65 of M. gajardoi , 27 of M. parapatrica, and 72 of M. spinolai , including adults and nymphs, in 13 localities located between 18º and 33º S of the coastal region and valleys in the interior of Chile.…”