Entomological study of Trypanosoma cruzi vectors in the rural communities of Sucre state, Venezuela

Abstract

Introduction: The ecological niche of Reduvidae vectors has been modified due to environmental changes and human encroachment into the rural areas.

Objective: This study evaluates the current entomological indices of triatomines responsible for Trypanosoma cruzi infection in Sucre State, Venezuela.

Materials and methods: A cross-sectional and prospective study was conducted in 95 towns and 577 dwellings in the 15 municipalities of the state of Sucre, Venezuela, from August to November, 2008. Triatomine bugs were identified on the basis of morphological characteristics, and their feces examined for T. cruzi infection through direct microscopy. Positive slides were stained with Giemsa and parasites were identified by morphologic characterization.

Results: The entomological indices expressing the highest values were dispersion (16.67%) and household colonization (33.33%). The triatomine species captured were: Rhodnius prolixus, Rhodnius pictipes, Rhodnius robustus, Panstrongylus geniculatus, and Triatoma maculata, the latter being the main intradomiciliaryvector.

Conclusions: Despite the low index of vector infection (1.72%), the existence of species with domiciliary and peridomiciliary reproductive success ensures the persistence of the epidemiological chain both for the disease and the parasite.