Reduced dengue incidence following deployments of -infected in Yogyakarta, Indonesia: a quasi-experimental trial using controlled interrupted time series analysis.

mosquitoes stably transfected with the intracellular bacterium ( Mel strain) have been deployed for biocontrol of dengue and related arboviral diseases in multiple countries. Field releases in northern Australia have previously demonstrated near elimination of local dengue transmission from -treated communities, and pilot studies in Indonesia have demonstrated the feasibility and acceptability of the method. We conducted a quasi-experimental trial to evaluate the impact of scaled releases on dengue incidence in an endemic setting in Indonesia. In Yogyakarta City, Indonesia, following extensive community engagement, Mel -carrying mosquitoes were released every two weeks for 13-15 rounds over seven months in 2016-17, in a contiguous 5 km area (population 65,000). A 3 km area (population 34,000) on the opposite side of the city was selected as an untreated control area. Passive surveillance data on notified hospitalised dengue patients was used to evaluate the epidemiological impact of deployments, using controlled interrupted time-series analysis. Rapid and sustained introgression of Mel into local populations was achieved. Thirty-four dengue cases were notified from the intervention area and 53 from the control area (incidence 26 vs 79 per 100,000 person-years) during 24 months following deployment. This corresponded in the regression model to a 73% reduction in dengue incidence (95% confidence interval 49%,86%) associated with the intervention. Exploratory analysis including 6 months additional post-intervention observations showed a small strengthening of this effect (30 vs 115 per 100,000 person-years; 76% reduction in incidence, 95%CI 60%,86%). We demonstrate a significant reduction in dengue incidence following successful introgression of into local populations in an endemic setting in Indonesia. These findings are consistent with previous field trials in northern Australia, and support the effectiveness of this novel approach for dengue control.