Omicron doesn't need to ruin the holidays: Here's what you need to know about rapid tests

As millions of people seek coronavirus tests before holiday trips to see family and friends, they are encountering familiar challenges of the pandemic – long testing lines and stores often sold out of home tests.

The highly contagious omicron variant has postponed professional sports games, canceled the Radio City Rockettes' remaining Christmas performances and shut down in-person finals week at several colleges.

Public health experts haven’t recommended people avoid holiday travel but urged them to be aware of risks and take steps to mitigate spread: Get vaccinated, get booster shots, wear masks and get tested if you feel sick or have been exposed to the virus.

Consumers have more testing options than ever but barriers persist. Long lines that were common early in the pandemic have again surfaced at testing sites in New York and Massachusetts. Others who choose the convenience of rapid home tests find the most popular versions are often sold out online and at stores.

Nevertheless, an average of 1.5 million Americans got tested for COVID-19 each day over the past week, according to Johns Hopkins University's testing tracker that compiles testing data reported by federal, state and local governments. The official tally does not include Americans who take home tests and don't report results, so the actual totals are higher.

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On Tuesday, President Joe Biden announced a plan to bolster testing with the purchase of a half-billion home coronavirus tests. Consumers will be able to order the tests through a new website and kits will be mailed to homes. His administration also will open new federal testing sites with the first location in New York City this week.

Experts who track testing say the nation’s supply remains uneven 20 months into the pandemic as demand soars for holiday travel, schools and businesses returning employees to work. And the testing shortage comes as the fast-spreading omicron variant accounts for about 3 out of every 4 new COVID-19 cases.

Dr. Michael Mina, an infectious disease expert and former Harvard professor who now serves as chief science officer of the testing company eMed, has long called for the federal government to take more aggressive steps to ensure home tests are widely available.

“Testing, in particular, is perhaps the most critical public health tool to support our vaccine efforts to limit transmission,” Mina said. “Testing is our eyes on this virus and if we can't see it, then we're flying blind.”

Here are some common questions people might have about testing:

What kind of tests can I get?

Molecular PCR tests are often administered at clinics, doctors’ offices, hospitals, or large-scale testing sites. These tests are completed at a lab and typically deliver results in a day or two, but processing can take a week or longer during periods of peak demand.

Rapid antigen tests detect a viral protein on the surface of the coronavirus. Testing kits can be deployed more quickly and are less expensive than lab tests. Consumers don’t need a prescription to purchase these tests, which are sold by major retailers or online.

What are the tests' strengths and weaknesses?

Molecular PCR tests are more sensitive and can detect traces of the virus over a longer period during the course of an infection. But these tests often require medical oversight, take longer to complete and are more expensive, often costing $100 or more per test. Insurance usually covers the cost when used to diagnose COVID-19, but insurers at times don't pay for tests used to screen people returning to work, school or for international travel. Some less-expensive molecular tests are authorized for home use. Detect Inc., a Connecticut tech company, sells its molecular test for $49 per test, plus $39 for a reusable testing hub.

Antigen tests typically deliver results in about 15 minutes and don't require a lab. The tests also are less expensive than lab tests. Abbott's BinaxNow COVID-19 self test and Quidel's QuickVue home test each cost $23.99 plus tax for a two-test kit at several retailers; Walmart sells the BinaxNow kit for $14.

While rapid antigen tests are less sensitive – meaning they are slightly less likely to detect the virus when compared to PCR tests – advocates say they are accurate enough to detect the virus when a person is infectious and likely to pass it to others.

Because home antigen tests are performed outside a lab and without medical oversight, "it's critical that all consumers follow the directions explicitly and read the directions before you test, understand how to interpret the results and know the next steps to take if needed," said Dr. Emily Volk, president of the College of American Pathologists. Anyone who tests positive on a home test should contact their doctor and may want to get a lab test to confirm the results, she said.

Why are home tests harder to find?

The two largest manufacturers, Abbott and Quidel, slowed production this spring as coronavirus cases dropped significantly. The manufacturing cutbacks followed a Centers for Disease Control and Prevention recommendation that vaccinated people did not need to get tested. The CDC later reversed its guideline as more breakthrough cases emerged.

Home test shortages surfaced this summer when the delta variant increased cases and more people sought testing. Although the Food and Drug Administration has given emergency use authorization to more than a dozen home test manufacturers, home tests are still frequently sold out at major retailers. Abbott remains the dominant test manufacturer. Citing Nielsen figures, Abbott CEO Robert B. Ford said during the company's October earnings call that Abbott controlled about 75% of the home testing market.

"We’re seeing unprecedented demand, and we’re sending out the tests as fast as we can make them," said John Koval, an Abbott spokesman.

Koval said Abbott is running U.S. factories 24/7 and expects to ramp up production to 70 million tests in January, up from current monthly totals of more than 50 million tests.

I still want to gather for the holidays, what should I do?

Because omicron is spreading so quickly and efficiently, it raises the odds that you will come into contact with the virus. If you do plan to attend a holiday gathering, get vaccinated and boosted and encourage friends and family to do the same.

"That's probably not going to prevent people from getting this virus, but I would much rather have a mild cold then be worried about prospects of going to a hospital," said Dr. Jennifer Nuzzo, an epidemiologist and senior scholar at the Johns Hopkins Center for Health Security.

Nuzzo and Mina recommend people get tested right before a gathering instead of a few days beforehand. One example might be to administer rapid tests in a car before entering someone's house. Although home antigen tests are not perfect, "perfect is not the goal. We need everyone to be a bit better," Nuzzo said.

If you live in a warm-weather state, try to spend time outdoors. Once inside, open windows to improve air flow and wear a mask as much as possible.

People should be especially cautious in crowded airports before boarding a plane, Nuzzo said. "I'm always much more worried about the airports than I am about the plane."

While waiting to board, Nuzzo wears a mask and tries to distance from others. Once on board, she recommends keeping a mask on, especially when nearby passengers take off theirs.

Mina acknowledges no strategy is perfect and said people should make decisions based on their health status and the health of their friends and families. But he said frequently using home tests will give people better odds of keeping themselves and others healthy.

"We're not looking for perfect. We're looking for the greatest risk-reduction strategies," Mina said. "Perfect is saying holed up in your room and not moving. But (nearly) two years into this, it's no longer what most people are willing or even should be considering."

Ken Alltucker is on Twitter as @kalltucker or can be emailed at alltuck@usatoday.com.

This article originally appeared on USA TODAY: Rapid COVID tests hard to find as millions travel amidst omicron