Testing and Nonpharmaceutical Interventions for Prevention of SARS-CoV-2 in 20 US Overnight Camps in Summer 2021

Overnight camps are a setting where COVID-19 can easily spread without the diligent use of layered public health interventions. We evaluated 20 camps in the United States to examine COVID-19 transmission and mitigation strategies during summer 2021.

For this descriptive cross-sectional study, we examined self-reported information from 20 camps in 6 predominantly northeastern states on geographic information, tests and testing cadences, vaccination rates, and number of COVID-19 cases during summer 2021. Because the camps had hired public health consultants to guide them on reducing COVID-19 introduction and spread, all camps implemented similar interventions, including encouraging behaviors that lower the risk of COVID-19 transmission prior to camp arrival, use of cohorts, testing before and after arrival, and strong encouragement of vaccination among eligible campers and staff members.

A total of 9474 attendees at the 20 camps came from geographically diverse regions. Camps generally tested before and at arrival, as well as once or twice after arrival. Rates of vaccination were high among staff members (84.6%) and campers (76.2%). Camps identified 27 COVID-19 cases, with 17 (63.0%) detected after arrival, 3 (7.4%) detected on arrival, and 8 (29.6%) detected prior to arrival.

The spread of cases detected after arrival to overnight camps was limited by the use of 3 key interventions: (1) high vaccination rates, (2) a rigorous and responsive testing strategy, and (3) ongoing use of public health interventions. These findings have implications for successful operation of overnight camps, residential schools and colleges, and other similar settings.