Modelling the effect of density vegetation coverage and the occurrence of peridomestic infestation by Triatoma infestans in rural houses of northwest of Córdoba, Argentina

Abstract

To better understand the dispersion strategies of Triatoma infestans (Klug) (Hemiptera: Reduviidae, Triatominae), we evaluated the spatial effect of infested peridomicile and density vegetation cover in a historically endemic area for Chagas disease. The study was conducted in rural houses of the northwest of Córdoba province, Argentine, during 2012-2013. Active search of triatomines were made in domicile and peridomicile habitats. To characterize vegetation coverage, a thematic map was obtained considering fi ve types of vegetation cover (closed/open forest, closed/open shrubland and cultural land).From each house we extracted the area of vegetation coverage, housing density and infested peridomiciles density. We used generalized linear models to evaluate the effect of these variables on the occurrence of infested peridomicile.According to our results, the probability of a peridomicile to be infested increases by 1.34 (95%CI [0.98; 1.90]) times more when peridomicile structures are in environments with higher housing density and by 1.25 (95%CI [0.84; 1.88]) more times when houses are surrounded by open shrublands. Among the multiple ecological determinants of peridomestic infestation, the infl uence of vegetation cover has been poorly studied.In this study we discussed the effect of the vegetation as a potential modulator of the dispersion strategies of T. infestans.

Domestic (re)infestation risk with the main vector Triatoma infestans increases with surrounding green vegetation and social vulnerability in the Argentine Chaco

“… Since a considerable percentage of the study houses (15.1%) lacked peridomestic structures, peridomestic infestation was not included in the models although peridomestic infestation is usually associated with domestic infestation and reinfestation processes with T. infestans [ 72 ]. Recently, peridomestic infestation by T. infestans was associated with vegetation cover type around rural houses in northwest Córdoba (Argentina) with higher infestation risk observed in peridomiciles immersed in open shrubland [ 73 ]. NDVI has been widely used to measure the density of green vegetation; it may not differentiate between certain vegetation types [ 14 ].…”