Vaccine scarcity during disease outbreaks forces difficult decisions about optimal distribution strategies, with implications extending far beyond individual protection to community-wide disease control. The 2022 mpox outbreak in New York City became an unintended natural experiment in vaccination strategy, providing crucial insights for future emergency responses.
Researchers used network transmission modeling to analyze NYC's controversial decision to prioritize first doses over complete two-dose vaccination courses during the JYNNEOS vaccine shortage. Their analysis reveals that the single-dose strategy prevented 66% of potential mpox cases compared to no vaccination. More significantly, this approach averted 17% more cases than a strategy that would have reserved doses to ensure complete two-dose vaccination for a smaller high-priority population subset.
This finding challenges conventional vaccination wisdom that prioritizes complete immunization protocols. The mathematical modeling suggests that broader population coverage with partial protection often outperforms narrower coverage with optimal protection during supply-constrained outbreaks. The research provides quantitative evidence supporting epidemiological principles about herd immunity thresholds and network effects in sexually transmitted infections. However, the analysis relies on modeling assumptions about vaccine effectiveness that may not translate to other pathogens or populations. The 17% advantage, while statistically significant, represents a relatively modest improvement that could vary substantially across different outbreak contexts, population networks, and vaccine characteristics. For emergency preparedness planning, this study reinforces the critical importance of flexible vaccination strategies that can adapt to real-world supply constraints rather than rigid adherence to optimal clinical protocols designed for abundant vaccine scenarios.