Significant Chagas Disease Transmission by a Previously Overlooked Vector

We conducted a cross sectional serological and entomological survey for Chagas disease in four communities in Northern Peru. Human as well as domestic animal sera were tested for the presence of antibodies against Trypanosoma cruzi by ELISA and western blot, and intestinal contents of triatomines were examined for the parasite by microscopic analysis. A total of 529 people participated in the study, 108 dogs and 207 guinea pigs were sampled for blood, and 213 houses were searched for the triatomine vector. We found that 15.7% (83) of community members were seropositive for T. cruzi infection, as well as 13.8% (15) of dogs, and 3.3% (7) of guinea pigs. 39.9% (85) of households searched were infested with triatomine insects, and in 38.5 % of infested houses, at least one triatomine was found to be carrying T. cruzi. The sole species of triatomine vector encountered within the houses was Panstrongylus herreri, a species that was previously believed to be predominantly sylvatic. This is one of the first studies documenting extensive T. cruzi infection mediated by P. herreri.