Factors associated with the occurrence of Triatoma sordida (Hemiptera: Reduviidae) in rural localities of Central-West Brazil

Juliana Chedid Nogared Rossi,Elisabeth C Duarte,Rodrigo Gurgel-Gonçalves

doi:10.1590/0074-02760140395

Juliana Chedid Nogared Rossi, Elisabeth C Duarte + Show 1 more

Open Access

https://doi.org/10.1590/0074-02760140395

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Abstract

This study estimates the factors of artificial environments (houses and peridomestic areas) associated with Triatoma sordida occurrence. Manual searches for triatomines were performed in 136 domiciliary units (DUs) in two rural localities of Central-West Brazil. For each DU, 32 structural, 23 biotic and 28 management variables were obtained. Multiple logistic regression analysis was performed in order to identify statistically significant variables associated with occurrence of T. sordida in the study areas. A total of 1,057 specimens (99% in peridomiciles, mainly chicken coops) of T. sordida were collected from 63 DUs (infestation: 47%; density: ~8 specimens/DU; crowding: ~17 specimens/infested DU; colonisation: 81%). Only six (0.6%) out of 945 specimens examined were infected with Trypanosoma cruzi. The final adjusted logistic regression model indicated that the probability of T. sordida occurrence was higher in DU with wooden chicken coops, presence of > 30 animals in wooden corrals, presence of wood piles and presence of food storeroom. The results show the persistence of T. sordida in peridomestic habitats in rural localities of Central-West Brazil. However, the observed low intradomestic colonisation and minimal triatomine infection rates indicate that T. sordida has low potential to sustain high rates of T. cruzi transmission to residents of these localities.

Highlights

Chagas disease (CD) is endemic in rural populations inhabiting structurally deficient households that favour the colonisation of triatomine bugs
The presence of wooden chicken coops (89%) and structures covered with asbestos tiles (46%) were very common
The domiciliary units (DUs) features according to the variables related to structural, biotic and environmental management factors in each locality are present in Supplementary Tables I-III

Summary

Introduction

Chagas disease (CD) is endemic in rural populations inhabiting structurally deficient households that favour the colonisation of triatomine bugs. In 2006, the Pan American Health Organization declared that Brazil was free from Trypanosoma cruzi transmission by the domestic vector Triatoma infestans (Dias 2007) Native species, such as Panstrongylus megistus (Villela et al 2009), Triatoma sordida (Oliveira & Silva 2007), Triatoma brasiliensis and Triatoma pseudomaculata (Silva et al 2012), continue to be found in domestic and peridomestic environments. The relative importance of biotic, structural and environmental management factors influencing the occurrence of this species in Central-West Brazil has not been systematically evaluated; such research could result in more effective control procedures and lead to more reliable predictions of the likelihood of household infestation. The aim of this study was to estimate the association between structural, biotic and environmental management factors and the presence of T. sordida in households in rural localities of the municipality of Posse, in the Brazilian state of Goiás (GO), Brazil

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