New recommendations call for three home tests for people exposed to the coronavirus. The third test will improve accuracy, the FDA says.
The CDC has updated its COVID-19 guidance in an effort to make things less confusing to Americans. Here’s what the agency recommends.Health officials have repeatedly cautioned that the tests can give false negatives if taken too early. The Centers for Disease Control and Prevention recommends people without symptoms wait to test until five days after an exposure. That’s because it generally takes several days before the antigens reach levels that are detectable via testing with a nose swab.
All 22 home antigen tests on the U.S. market were authorized for emergency use based on preliminary data, while companies and researchers gathered more definitive metrics on their accuracy. The FDA said its latest decision reflects new information. In a government study, adding a third test improved accuracy from 62% to 79%.