Triatoma dimidiata (Latreille) Abundance and Infection with Trypanosoma cruzi in a Rural Community of Yucatan, Mexico

The present is a longitudinal study that describes the abundance of Triatoma dimidiata (Latreille) (Hemiptera: Reduviidae) and its infection with Trypanosoma cruzi in a rural community of Yucatan, Mexico. From a total of 370 individuals collected, 81.3% were adults, most from intradomicile ecotope (282/301), but nymphs were more abundant in peridomicile (58/69). The overall proportion of infected bugs was 21.9% (23.9% of adults and 13% of nymphs). The infection proportion was similar between intradomicile and peridomicile ecotopes (22.8% and 18.1%, respectively). Overall, 76.5% (36/47) of the houses and their backyards were infested. Of those, 27.7% were colonized and 75% had infected triatomines. Our data showed different proportions on infestation, colonization and bug density. Ninety-seven percent of overall peridomicile abundance was distributed in chicken coops, doghouses, opossum nests and dove cages. Triatomine entomological indices showed higher infestation and density inside domiciles, but higher colonization in the peridomicile. The abundance, the amount of infected intradomicile adult T. dimidiata and the incidence of infestation showed a seasonal pattern, with 63.7% of all individuals collected during the late dry season (April to June). We showed the peridomicile colonization of animal shelters and suggest it as a relevant source of T. dimidiata individuals. As infected bugs were found in both ecotopes, the studied area is under a high risk of T. cruzi transmission to humans.