Imperviousness as a predictor for infestation levels of container-breeding mosquitoes in a focus of dengue and Saint Louis encephalitis in Argentina

Abstract

Dengue and Saint Louis encephalitis virus are among the mostimportant emerging viruses transmitted by mosquitoes at the global scale, and from 2009 onward both diseases have reached temperate Argentina. To test whether the urbanization level can be used as a predictor for the infestation levels of containerbreedingmosquito vectors, we searched for Aedes aegypti and Culex pipiens in 8400 water-filled containers from 14 cemeteries of Buenos Aires Province and we used generalized linear models to relate positive containers withthe impervious area quantified inside (internal PIA) and outside (external PIA) cemeteries. The bestmodelfor Ae. aegypti explained 91%ofthe variability and included the season,the internal PIAand the external PIA at 1 km as a quadratic function, showing a parabolic response peaking in ∼75%. Regarding the infestation levels of Cx. pipiens, the final model explained 75% of the variability and included only the season. In view of these results, the percentage of impervious area efficiently predicted the infestation levels of Ae. aegypti but not of Cx. pipiens. Considering the worldwide relevance of the former in dengue transmission, the simple quantification of imperviousness proposed herein provides a helpful basis for vector surveillance and control in urbanized areas.