173 - BugOut Wolbachia: Data-driven support for a community-driven project

BugOut Wolbachia is a community-driven campaign to eliminate Aedes aegypti from Virgin Gorda in the British Virgin Islands. The project is a partnership between Green VI, a non-profit NGO based in the BVI, and Verily’s Debug Team, a global team experienced in using Wolbachia male releases for suppression of Ae. aegypti. The program combines traditional source reduction efforts with mass trapping and incompatible male releases to suppress Ae. aegypti on Virgin Gorda. 

Phase 1 of our program launched in 2022 and established an island-wide surveillance program to capture data on male and female Aedes numbers using BG-Sentinel traps and egg hatch rates using ovitraps. We also conducted mark-release-recapture studies to evaluate dispersal and survival of packed and shipped male mosquitoes from Verily’s centralized production facility to the remote release sites on Virgin Gorda. 

Following 10 months of surveillance data collection and four replicates of MRR studies, we launched Phase 2 of our program with regular releases of Wolbachia males starting in January 2023. We have used BG-Sentinel and ovitrap data to track the impact of the program on hatch rates and numbers of biting females in release areas compared to untreated sites and compared to previous surveillance data in the same sites. We have shown significant reductions in both biting females and hatch rates in areas treated with Wolbachia male releases compared to untreated sites. We are continuing to conduct studies on the value of adding mass trapping efforts ahead of releases and ongoing work on source reduction to maximize the impact of released males.