The urgency of resuming disrupted dog rabies vaccination campaigns: a modeling and cost-effectiveness analysis

OBJECTIVE: Dog vaccination is a cost-effective approach to preventing human rabies deaths. In Haiti, the 2019 dog vaccination campaign did not include the capital city, and the 2020 campaign was cancelled because of COVID-19 lockdown restrictions and redirection of funds. We estimated the number of human lives that could be saved by resuming dog vaccination in 2021 compared to 2022 and compared the cost-effectiveness of these two scenarios. METHODS: We modified a previously published rabies transmission and economic model to estimate trends in dog and human rabies cases in Haiti from 2005-2025. We compared model outputs to surveillance data on human rabies deaths from 2005-2020 and animal rabies cases from 2018-2020. We then estimated the human health and cost implications of restarting dog vaccination programs in either 2021 or 2022. FINDINGS: Model predictions and animal surveillance data from Haiti both suggest a 5- to 8-fold increase in animal rabies cases has occurred in the capital city between Fall 2019 and Fall 2020. We estimate that restarting dog vaccination in Haiti in 2021 compared to 2022 could save 285 human lives and prevent 6,541 human rabies exposures over a five-year period and may decrease program costs due to reduced need for human post-exposure prophylaxis. CONCLUSIONS: A one-year delay in resuming dog vaccination in Haiti, from 2021 to 2022, could cost hundreds of lives over the next 5 years. Interruptions in dog vaccination campaigns before elimination is achieved can lead to significant human rabies epidemics if not promptly resumed.