December 20, 2021
The CDC announced Friday that students who are exposed to the coronavirus can still attend school as long as they continue to test negative for the virus in the following days.
The new guidance, known as the "test-to-stay" protocol, would reduce the number of children who are expected to stay home as a close contact to someone who tested positive for the virus.
"Test-to-stay is an encouraging public health practice to keep our children in schools," Rochelle Walensky, MD, director of the CDC, said during a White House press briefing.
When a COVID-19 case is identified in a school, the test-to-stay strategy allows schools to implement regular testing rather than quarantine close contacts. If the contacts don't experience symptoms and test negative at least twice in a seven-day period, they can continue in-person learning. If they test positive, then they are required to isolate.
In recent months, the CDC has collaborated with several school districts across the U.S. to evaluate test-to-stay programs. On Friday, the CDC published two studies in its Morbidity and Mortality Weekly Report that demonstrated the effectiveness of these programs in limiting the spread of the virus while also keeping students in class.
"CDC is updating our materials to help schools and parents know how to best implement this promising and now-proven practice, along with our multi-layer prevention strategies that will help keep our children in the classroom safely," Walensky said Friday. "These studies demonstrated that test-to-stay works to keep unvaccinated children in school safely."
In one study, researchers analyzed data for public schools in Los Angeles County between Aug. 16 and Oct. 31, where 432 schools implemented test-to-stay and 1,635 did not.
The Los Angeles County Department of Public Health found that COVID-19 cases did not increase among the schools that used the protocol, as compared with schools that didn't.
Before test-to-stay was implemented, the average daily number of cases was 10 cases per 100,000 students in districts that later adopted the protocol and 20 cases per 100,000 students in districts that didn't. After the program was implemented, average daily case rates declined in all school districts but remained lower in test-to-stay districts, with 6 cases per 100,000 students as compared with 11 cases per 100,000 students in districts that didn't do the protocol.
In addition, schools that didn't use the test-to-stay program "lost substantial in-person school days," researchers wrote. At the same time, implementing the program "requires resources that might be currently unavailable for some schools," they added, noting that "a higher percentage of disadvantaged schools" didn't do the protocol.
The program requires personnel who can track which students need to be tested, their results and when they can come off the list of close contacts, officials told CNN. This can be a challenge for overstretched school nursing staff.
In another study published Friday, researchers analyzed data between Aug. 9 and Oct. 29 for 90 schools across 31 districts in Lake County, Illinois, that implemented test-to-stay programs. During that time, the schools reported 258 COVID-19 cases and 1,664 close contacts.
The Lake County Health Department examined the number of close contacts that later tested positive and whether the virus further spread from the close contacts to other people. They found that 16 of the close contacts tested positive and that these were all students. No one appeared to transmit the virus to others at school, but nine cases were identified among household contacts.
Overall, study authors wrote, the test-to-stay protocol preserved in-person learning days for students. In addition, regular testing, masking, and physical distancing led to lower virus transmission in school.
"The test-to-stay-programs are really good at balancing the costs and benefits," Zoe McLaren, a health policy expert at the University of Maryland at Baltimore, told The New York Times.
"What the test-to-stay program does is help us keep COVID cases down, while also trying to make sure we keep kids in school as much as possible, which I think is really important," she said.