Speaker
Description
Smallpox, caused by the variola viruses, led to high mortality throughout human history. Although eradicated, virus samples are held in laboratories and accidental or deliberate release remains possible. Many countries therefore maintain smallpox vaccine stockpiles as part of preparedness planning.
Historically, vaccination strategies were constrained by the risks associated with first generation vaccines, which carried high rates of severe adverse events. Modern third generation vaccines have an improved safety profile, shifting the balance between vaccine risk and outbreak control.
Modelling studies in the 2000s explored the potential impact of a smallpox outbreak in a contemporary UK population. These analyses concluded that mass-vaccination was suboptimal, due to the associated risks. Additionally, they relied heavily on expert judgement to quantify key elements of the public health response, such as vaccination rollout and contact tracing. Experience from the COVID-19 pandemic has since provided detailed real-world data on the performance and limits of these interventions.
We developed a stochastic metapopulation model for Great Britain, combining the strengths of earlier modelling work with updated population mobility data and empirically informed estimates of response capacity. Simulating outbreaks seeded with between 1 and 200 index cases, we reassess response strategies and the role of vaccination in contemporary smallpox preparedness.
