Assessing the Efficacy of Male Wolbachia-infected Mosquito Deployments to Reduce Dengue Incidence in Singapore: a Cluster Randomized Controlled Trial

The study is designed as a parallel, two-arm, non-blinded cluster-randomised controlled trial to be conducted in high-rise public housing estates in Singapore. The aim is to determine whether large-scale deployment of male Wolbachia-infected Ae. aegypti mosquitoes can significantly reduce dengue incidence in intervention clusters. The investigators will use the cluster-randomised design, with the study area comprising 15 clusters with a total area of 10.9 km2, covering approximately 722,000 residents in 1,700 apartment blocks. Eight clusters will be randomly selected to receive the intervention, while the other seven will serve as non-intervention clusters. Intervention efficacy will be estimated through two primary endpoints: (1) odds ratio of Wolbachia exposure distribution (i.e. probability of living in an intervention cluster) among laboratory-confirmed reported dengue cases compared to test-negative controls, and (2) laboratory-confirmed reported dengue counts normalized by population size in intervention versus non-intervention clusters.