Many families will ring in the holidays this year with a new tradition: before eggnog and gifts, they will put a pretty cotton swab in their nose. Rapid COVID-19 antigen tests – the ones you can buy at a drugstore and take home – are less sensitive than the diagnostic polymerase chain reaction, or PCR, tests you get at a clinic.

But they’re faster, more convenient, and they turn positive when people are most likely to be contagious, all of which are important factors for families coming together as the immune-evasive omicron variant begins to spread. However, the limited supply and relatively high cost could limit the usefulness of such tests this holiday season.

Justin Noggle in Kansas City has added quick tests to his Christmas shopping list. Because he and his girlfriend will be seeing older parents and unvaccinated children, they want the added assurance of a negative test.

“We’re nervous, but we’re not ready to sacrifice yet another holiday,” Noggle said. “Our plan is to – after learning that there might be testing – is to go out early on Saturday morning, go and look online and in all the different pharmacies.”

Rapid tests were regularly sold out in stores and online a few months ago, but supplies have improved recently, said Lindsey Dawson with the Kaiser Family Foundation. Yet rapid tests can still be difficult to detect when demand increases, as it is now.

“It’s not a good indicator when a store says a test is available in a particular zip code, in a particular store, for that test to actually be there,” she said.

And then there is the cost. Dawson said prices range from around $ 7 to $ 30 per test. A plan by the Biden administration to force insurance companies to reimburse consumers will not be implemented until next year and will only help about half of Americans who have private insurance.

“We continue to neglect testing as a public health tool that is essential, to leave testing to the whims of free markets,” said Michael Mina, a former Harvard epidemiologist now with digital health platform eMed .

He said a slow regulatory process resulted in a limited number of companies approved to perform the testing, and without federal investment they couldn’t produce on the scale needed to bring prices down and make them readily available.

In fact, at the start of the summer, a manufacturer in fact destroyed millions of tests and laid off workers when demand fell, only to see it explode again with the spread of the delta variant.

“If we are to put public health into a for-profit or non-profit industry, we have to strengthen that industry,” Mina said.

Some local communities are filling the void. In Colorado, residents can order up to eight free tests per week, said Sarah Hamma of the State Department of Public Health and Environment.

“It’s super quick and easy. You fill out a quick form and then our distribution partner will deliver this product right to people’s homes, ”she said.

The state has spent about $ 10 million to send 1.2 million tests since September.

Research co-authored by Michael Mina for the National Bureau of Economic Research suggested expenses for rapid tests would save several times more than the initial investment by reducing the burden of disease and economic damage.