Respiratory mortality in prisons during the 1918-1919 influenza pandemic

Prisons are among the most controlled human environments, and prisoners often suffer epidemic disease when influenza is introduced into these restricted populations. A review of contemporary records of five prison systems during the 1918-1919 influenza pandemic showed that most prison populations did remarkably well under lockdown, with few resulting respiratory deaths. Exceptional prisons with high respiratory mortality included the Andaman Islands prison colony (17.3/1000) and the US Army Disciplinary Barracks (42/1000) at Fort Leavenworth, Kansas. Factors that likely resulted in high respiratory mortality included the absence of earlier waves of influenza-like illness and increased prisoner turnover introducing additional respiratory bacteria strains. Prison staff often had influenza rates that were very different to those of the prisoners they were guarding. Although free populations resented social restrictions during the COVID-19 pandemic, controlling population movements can serve to limit respiratory pathogen spread while waiting for alternative public health measures such as immunisations to arrive.