Can we trust rapid COVID tests against BA.2? This is what the experts say

Rapid tests are effective in detecting BA.2 but it can jump from person to person before a positive result is detected.

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The omicron BA.2 subvariant is the dominant strain in the U.S. and has been for a while. Rapid at- home antigen tests are the first choice diagnostic tool for many people who think they might be infectious.

While these rapid tests are useful in detecting the spread of COVID-19, the high infectivity of BA.2 and concerns around self-reporting have given rise to a number of questions.

Two health experts have something to say.

Rapid antigen tests work against BA.2, but there are some caveats

Although we know that rapid tests have a lower degree of accuracy compared to the standard test, there is no indication that they are any less effective at detecting BA.2 than previous versions.

According to Dr. Gounder, a senior fellow and editor-at-large for public health at Kaiser Health News, rapid tests might take longer to yield a positive result.

There is usually a day or two delay between when you can get a positive result on a rapid test and when you can get a negative result.

There is a chance that a positive result on a rapid test for the BA.2 virus could be a sign that the virus is spreading, according to a doctor who works with the federal government.

The BA.2 subvariant is more infective than the other previous versions and the test might not have time to pick it up before it jumps from one person.

The advantage of rapid tests is that they are widely available and can deliver a result within minutes. To use them effectively against BA.2 you need to test early and often.

Each person can test themselves multiple times if they can get hold of these things.

The accuracy of these types of tests is mitigated by the fact that they are serial.

Have some symptoms but test is negative? Context is key

Some people may have symptoms that are consistent with a COVID-19 infection, but they are still negative on rapid tests. Context is the key to determining what to do next if you find yourself in a situation like this.

People who are immunocompromised should still be watched.

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If you continue to test negative, he said you might be able to carry on with your daily life, as long as you don't plan on being around people who are immunocompromised.

Extra precautions should be taken for the sake of people who are at higher risk of severe illness.

If you are going to visit an elderly family member who has cancer, I would recommend taking some extra precautions, even if you are negative.

If people aren't reporting the results from their rapid tests, can we trust the data?

The current data might not reflect actual infections if there is a lack of self- reporting.

This is an important question that the governmental, medical and public health communities are just now scratching the surface of.

There isn't any requirement to report a positive result in some rapid tests.

The Centers for Disease Control and Prevention encourages people to report any positive results to their health care providers, who can make sure they receive the appropriate medical care. Specific treatments could be included.

The public health community, including the CDC, is confident that situational awareness remains strong without receiving self-test results.

New tests work best. But expired tests might still work for a time

Every household in the U.S. can order two sets of four free at- home tests through covid.gov. Additional tests are not free.

Gounder and Lam both agree that it is best to follow the manufacturer's suggested expiration date. If you have an old rapid test on hand, they say it could be useful for a while.

The rapid tests are similar to food products and will not go bad immediately after the expiration date.

Gounder suggests storing the tests in chronological order.