At-home COVID-19 tests add another layer of precaution

For many people, the hardest part of pandemic life after vaccination is the uncertainty about risk. But rapid home testing can lower risk, ease the worry and help you get back to life.

Testing is not a substitute for getting the vaccine. But as long as large numbers of peo- ple remain unvaccinated and continue to spread the coronavirus, vaccinated people are at risk for so-called breakthrough infections, which often come with mild symp- toms or none at all.

For the vaccinated, a nega- tive test is like a one-day anxiety-free pass. At-home rapid tests can tell people within minutes whether they are con- tagious with COVID-19. If you have been traveling through airports or you have recently spent time at a crowded outdoor concert, a few rapid tests, taken days apart, can show that you are unlikely to be spreading the coronavirus after attending those high- er-risk events.

One big problem is that the tests can be hard to find, but that should improve soon with the authorization of a new test and an investment of $1 billion in home testing from the Biden administration.

Some stores do still have tests in stock, but it may require some effort to find them. If you find a stash of tests, do not hoard. Tens of millions more tests are expected to arrive on the market in the coming weeks, and by Decem- ber, 200 million rapid tests will be available to Americans each month.

No test is a 100% guaran- tee, but given that your vaccine already protects you, a home test is another layer of precaution to lower risk. Unvaccinated people can benefit from using home tests as well, but they should not rely on testing as a substitute for a vaccine. Home tests are par- ticularly useful for families with young children who are not yet eligible for vaccination and for anyone with an at-risk family member.

In the United States, the tests can range from $7 to $12 each, making them too expensive for most people to use frequently. But with cold weather approaching and winter holidays ahead, home tests still can be a helpful way to lower the risk of indoor gatherings.

How do they work?

The rapid home tests work much like a pregnancy test, with a pink line indicating you are positive for the coronavirus. The tests all require you to swizzle a swab in both nostrils. Depending on the test, you may insert the swab into a special card reader or dip the swab in a solution and use a test strip, then wait 10-15 minutes for the result.

The rapid home antigen tests available in the United States include Abbott’s BinaxNOW, Quidel’s Quickvue, Australia’s Ellume and the recently authorized test by Acon Labs, Flowflex. The tests typically are packaged two per box.

A rapid home molecular test, Lucira, uses a different technology and is similar to the test you might get at the doctor’s office. But it is hard to find, and at a cost of about $50, it is not a practical option for most people.

Are home tests reliable?

Although no test is 100% accurate, the new rapid home tests are highly reliable for telling you whether you are contagious on a given day. Rapid tests identify about 98% of cases in which a person is infectious.

But it is also possible to test negative on one day and then test positive a few days later. That does not mean the first test was wrong; it just means on the day you tested, you were not infectious yet.