"Using the next-generation method to explore synergy of vector control methods against Aedes-borne diseases"
The evidence for vector control methods aimed at reducing the burden of Aedes-borne diseases largely consists of studies that measure entomological endpoints for a single intervention. In practice, in the effort to control outbreaks, multiple vector control methods are often implemented simultaneously, and it is currently not well understood how different vector control methods interact with each other to reduce disease burden. To address this, we conducted a systematic literature review to obtain estimates of entomological parameters under the impact of eight different vector control methods to calculate transmission coefficients under a Ross-Macdonald formulation. Using the next-generation method, we calculated the reproduction number under the impact of pairs of interventions for a range of coverage levels to determine which combinations resulted in the greatest reduction of transmission. Initial results suggest that as coverage of interventions that increase mortality during early life stages, such as larviciding, increases, interventions that primarily derive their effects from their impacts on vectors during later life stages, such as spatial repellents, exhibit smaller impacts. On the other hand, the impact of interventions that act on overlapping life stages increases as coverage of both interventions increase. Utilizing the next-generation method allows us to effectively investigate potential synergies between pairs of interventions. This method could be extended to exploring synergies between interventions for other infectious diseases.
Additional authors: Erin Coyne, University of Notre Dame Department of Biological Sciences and Eck Institute of Global Health; Hannah Clapham, National University of Singapore Saw Swee Hock School of Public Health; T. Alex Perkins, University of Notre Dame Department of Biological Sciences and Eck Institute of Global Health