https://www.sciencedaily.com/releases/2022/02/220208191733.htm

In early 2020, Georgia Tech researchers designed a saliva-based polymerase chain reaction (PCR) test and encouraged community members to test weekly to track the health of the campus. Their strategy confirmed 62% of the campus' positive cases in the Fall 2020 semester. The method of surveillance testing -- focusing on case clusters and then having patients isolate -- reduced positivity rates from 4.1% in the beginning of the semester to below 0.5% mid-semester. Their findings were published in the journal Epidemiology.

"One of the ways you can mitigate spread is not to think about testing as just an indicator for how bad things are, but actually use enough testing that you can begin to pull infected people out of circulation to reduce the spread," said Joshua Weitz, Georgia Tech professor in the School of Biological Sciences who developed the infectious disease models used to monitor campus.