Using Lateral Flow Devices to Enhance Molecular Epidemiology and Evaluating the Rabies Surveillance System on Unguja Island, Zanzibar.

Dog rabies remains a neglected tropical disease in many resource-limited endemic regions, including Unguja Island, Zanzibar. Classically, in such resource-limited settings, an underestimation of the impact of rabies, which directly correlates with insufficient diagnostic capabilities and surveillance efforts, leads to poor investment in effective rabies control. This study combined molecular epidemiology with retrospective analyses of surveillance data from 2016 to 2024 to better understand the transmission dynamics and assess the effectiveness and reliability of the rabies surveillance system on Unguja Island. Towards this goal, rabies RNA was extracted from used lateral flow devices for further molecular phylogenetic analyses of the partial nucleoprotein gene. From this analysis, we were able to conclude that the rabies lyssaviruses presently circulating on Unguja Island represent a distinct endemic cycle in comparison to rabies viruses from elsewhere in Tanzania. In addition, space-time analysis and the evaluation of testing rates identified high-risk rabies areas with particularly inadequate surveillance. These findings allow better understandings of the disease's impact, which will support improved surveillance and the implementation of targeted control strategies, and will pave the way for, hopefully, the elimination of dog rabies in the longer run.