Dynamic mapping of the probability of infestation by urban arbovirus vectors in the municipalities of Rio Grande do Sul state, Brazil, 2016-2017

Abstract

Objective  To compare official mapping with probabilistic mapping of infestation by Aedes spp. in the municipalities of Rio Grande do Sul state, Brazil.

Methods  This was an ecological study using data from samples of mosquito breeding sites collected in 2016-2017; official classification was obtained from epidemiological reports, and infestation per municipality and week was estimated by fitting a dynamic site-occupancy model to data from municipal epidemiological surveillance.

Results  187,245 samples collected in 473 municipalities returned 10,648 detections of Aedes aegypti, and 8,414 detections of Aedes albopictus; official mapping agrees with probabilistic mapping in municipalities in the northwestern and western regions of the state. The mappings are not in agreement in the eastern, central, northeastern and southern regions, revealing municipalities officially not infested but with high probability of infestation and notification of arbovirus infection.

Conclusion  While official classification identified critically infested municipalities in the state’s northwestern and western regions, it did not identify infestation in municipalities with possible false zero errors and where infestation varies over time.