The Centers for Disease Control and Prevention and the National Institutes of Health announced a new initiative on Wednesday to help determine whether frequent, widespread use of rapid coronavirus tests slows the spread of the virus.
The program will make rapid at-home antigen tests freely available to every resident of two communities, Pitt County, N.C. and Hamilton County, Tenn., enough for a total of 160,000 people to test themselves for the coronavirus three times a week for a month.
“This effort is precisely what I and others have been calling for nearly a year — widespread, accessible rapid tests to help curb transmission,” said Michael Mina, an epidemiologist at Harvard University who has been a vocal proponent of rapid, at-home testing programs.
He added, “Taking 30 seconds out of your day three times a week to perform the test is something any person can do.”
Antigen tests are cheaper and faster than P.C.R. tests, which are the gold standard for diagnosing Covid-19, the disease caused by the virus, but they are less sensitive and more prone to false negatives. Mathematical models have suggested that if these tests are used frequently, they can still reduce transmission of the virus.
The tests can help identify people who may not realize that they are infectious, prompting them to self-isolate before they are able to transmit the virus to others. But real world data has been limited, and with virus case numbers still high across the country, testing remains essential, public health experts say.
“We have all hypothesized that testing at home, at scale could stop the chain of transmission of the virus and allow communities to discover many more cases,” said Bruce Tromberg, who directs the National Institute of Biomedical Imaging and Bioengineering and leads its rapid acceleration of diagnostics program, which is supplying the tests for the initiative. “All the mathematical models predict that. But this is a real world, real life example.”
Residents who decide to participate in the program can have the tests delivered to their homes or pick them up at local distribution sites. An online tool will guide participants through the testing process and help them interpret their results. Residents can also volunteer to complete surveys that will assess whether frequent testing has changed their behavior, knowledge about Covid-19, or opinions on vaccination.
Researchers at the University of North Carolina and Duke University will compare the test positivity, case and hospitalization rates in these two communities to those in other similar communities that are not participating in the program.
A. David Paltiel, a professor of health policy and management at Yale School of Public Health, called the launching of a real-world study of the effectiveness of rapid, at-home screening. “just great news.” But he cautioned that the results will need to be interpreted carefully, especially if the residents who choose to participate in the initiative are not representative of the community at large.
“We know that self-selection tends to bring out the worried well and a disproportionate number of people who are already Covid-conscious or Covid-conscientious,” he said.
“It’ll be great to see how it works when in the hands of people who really care,” he added. But, he said, the results may not be widely generally applicable to screening programs in which participation is mandatory, as may be the case with some workplace and school programs.