Optimizing the deployment of ultra-low volume and indoor residual spraying for dengue outbreak response

by Sean M. Cavany, Guido Espa ña, Alun L. Lloyd, Lance A. Waller, Uriel Kitron, Helvio Astete, William H. Elson, Gonzalo M. Vazquez-Prokopec, Thomas W. Scott, Amy C. Morrison, Robert C. Reiner Jr., T. Alex Perkins Recent years have seen rising incidence of dengue and large outbreaks of Zika and chikungunya, which are all caused by viruses transmitted byAedes aegypti mosquitoes. In most settings, the primary intervention againstAedes-transmitted viruses is vector control, such as indoor, ultra-low volume (ULV) spraying. Targeted indoor residual spraying (TIRS) has the potential to more effectively impactAedes-borne diseases, but its implementation requires careful planning and evaluation. The optimal time to deploy these interventions and their relative epidemiological effects are, however, not well understood. We used an agent-based model of dengue virus transmission calibrated to data from Iquitos, Peru to assess the epidemiological effects of these interventions under differing strategies for deploying them. Specifically, we compared strategies where spray application was initiated when incidence rose above a threshold based on incidence in recent years to strategies where spraying occurred at the same time(s) each year. In the absence of spraying, the model predicted 361,000 infections [inter-quartile range (IQR): 347,000 –383,000] in the period 2000–2010. The ULV strategy with the fewest median infections was spraying twice yearly, in March and October, which led to...
Source: PLoS Computational Biology - Category: Biology Authors: Source Type: research