CDC Study: A test to stay strategy (allowing close contacts with masked COVID-19 exposures to remain in school) was very efficacious in preventing further school spread and allowed children to stay in the classroom as an alternative to home quarantine.

Evaluation of Test to Stay Strategy on Secondary and Tertiary Transmission of SARS-CoV-2 in K–12 Schools — Lake County, Illinois, August 9–October 29, 2021 – CDC Morbidity and Mortality Weekly Report

Related CDC Study: Evaluation of a Test to Stay Strategy in Transitional Kindergarten Through Grade 12 Schools — Los Angeles County, California, August 16–October 31, 2021 – CDC Morbidity and Mortality Weekly Report

Related CDC Guidance:

What You Should Know About COVID-19 Testing in Schools – Centers for Disease Control and Prevention

Science Brief: Transmission of SARS-CoV-2 in K-12 Schools and Early Care and Education Programs – Updated – Centers for Disease Control and Prevention

Commentary: ‘Test-to-stay’ works to keep students in school safely, CDC director says – CNN

Related:

Instead of quarantine for Covid-exposed students, some schools are trying test-to-stay.

Cluster RCT: Daily contact testing of school-based contacts was non-inferior to self-isolation for control of COVID-19 transmission.

Kids are losing school days to quarantines. Here’s a way to keep them in classrooms – “Test-to-stay could dramatically reduce close contact quarantines”.

Opinion | Data from routine Covid testing can help schools stay open this year.

Commentary on Twitter

Although vaccination is the best way to protect against #COVID19 for those aged 5 and up, schools might consider Test to Stay strategy for allowing close contacts who are not fully vaccinated to remain in the classroom. Learn more in a new @CDCMMWR: https://t.co/3m64vomRDh. pic.twitter.com/AAENAdxJ1y

— CDC (@CDCgov) December 17, 2021