Outbreak of COVID-19 and Interventions in One of the Largest Jails in the United States: Cook County, IL, 2020

ABSTRACT

BackgroundCorrectional and detention facilities are disproportionately affected by COVID-19 due to shared space, contact between staff and detained persons, and movement within facilities of detained persons, many with pre-existing medical conditions. On March 18, 2020, Cook County Jail, one of the United States largest, identified its first suspected case of COVID-19 in a detained person. MethodsThis analysis includes SARS-CoV-2 cases confirmed by molecular detection among detained persons and Cook County Sheriffs Office staff. We examined occurrence of symptomatic cases in each building and proportions of asymptomatic detained persons testing positive. We describe timing of interventions including social distancing, mask use, and expanded testing and show outbreak trajectory in the jail versus contemporaneous case counts in Chicago. ResultsDuring March 1-April 30, 907 symptomatic and asymptomatic cases of SARS-CoV-2 infection were detected among detained persons (n = 628) and staff (n = 279), with nine deaths. Symptomatic cases occurred in all housing divisions; in 9/13 buildings, staff cases occurred first. Among asymptomatic detained persons in quarantine, 23.6% tested positive. Visitation stopped March 15, programmatic activities were suspended March 23, cells were converted into single occupancy beginning March 26, and universal masking was implemented for staff (April 2) and detained persons (April 13). Cases at the jail declined while cases in Chicago increased. ConclusionAggressive intervention strategies coupled with widespread diagnostic testing of detained and staff populations can limit introduction and mitigate transmission of SARS-CoV-2 infection in correctional and detention facilities.