Global Biodefense March 9, 2021 Using the monkeypox outbreak in Nigeria during 2017–2020 researchers in Australia built a statistical model to simulate declining immunity from monkeypox at 2 levels: At the individual level, they used a constant rate of decline in immunity of 1.29% per year as smallpox vaccination rates fell. At the population level, the cohort of vaccinated residents decreased over time because of deaths and births. By 2016, only 10.1% of the total population in Nigeria was vaccinated against smallpox; the serologic immunity level was 25.7% among vaccinated persons and 2.6% in the overall population. The substantial resurgence […]