Optimal deployment of limited vaccine supplies to control mpox outbreaks

Mpox outbreaks in central and East Africa have been declared a public health emergency of international concern by the World Health Organization. Fortunately, real-world effectiveness studies of the MVA-BN vaccine indicate that it has an effectiveness of 74% after one dose, and 82% after two doses against mpox. However, given the very limited availability of vaccines, there remain questions around the optimal deployment of limited MVA-BN doses. In this study, we consider whether more mpox cases might be averted by following the traditional two-dose vaccine regimen (4 week dosing interval), or by giving a single dose of MVA-BN to as many individuals as possible. We find that the optimal strategy depends on (i) the degree to which a subpopulation might be at higher risk of mpox, or severe mpox, and (ii) how long ago the first dose was administered to the most at-risk subpopulation.