Want to be sure you don't have COVID? FDA now says you'll need to pass 3 home tests

  • In Business
  • 2022-08-11 20:35:08Z

If you're taking an at-home COVID-19 test and want to be confident you're clear of the virus, you'll need not just one or two but three tests with negative results over five days before it's likely safe to hug grandma.

That's the new recommendation issued Thursday by the Food and Drug Administration. It follows a new study that concludes using three home COVID tests with 48 hours between tests for those without symptoms delivers a higher degree of accuracy than two tests over three days.

The recommendation for a third test is directed at those who fear they may have been exposed to the virus or want to leave no doubt about their negative status.

Even with that stipulation, Thursday's recommendation signals a significant shift in a system where home tests are mostly sold and distributed in two-test kits.

Home antigen tests are quick and inexpensive but less sensitive than polymerase chain reaction or PCR tests, which are usually performed in a lab. While the FDA has cleared more than two dozen home antigen tests that detect proteins from the COVID-19 virus, it says the home tests are less accurate, especially in detecting a case early in an infection or in people who don't have symptoms.

That means people who have no symptoms and take a home test immediately after being exposed to the virus could get a false negative result. That's why the FDA had been recommending repeat testing, usually over 48 hours.

The new study, led by University of Massachusetts researchers, said the two-test kits typically sold at pharmacies or grocers are still highly accurate for people with symptoms. Study participants with symptoms who used home tests twice over 48 hours accurately detected COVID in 93% of cases in which the virus was found using more sensitive labs tests.

Yet among people who weren't showing symptoms, the accuracy fell to 63% for those who took two tests over 48 hours. Taking a third test two days after the second improved the accuracy to 79%.

The study drew more than 5,000 participants from a larger federal study funded by the National Institutes of Health. Participants tested themselves every 48 hours for 15 days using home tests. They also collected samples that were sent to a lab for comparative PCR testing.

Researchers said the higher sensitivity of using three tests over five days could catch more cases and inform infected people without symptoms to avoid contact with others, limiting spread.

"This was the type of data needed to instill confidence in antigen testing," said Dr. Apurv Soni, a UMass Chan Medical School assistant professor of medicine and a principal investigator on the study.

The study shows antigen testing works for those with or without symptoms, Soni said, but the key is communicating the right message. People without symptoms should take three tests with 48 hours lapsed between each test to be more certain they don't carry the virus.

Soni acknowledges it's "not a trivial change" to recommend three tests for people without symptoms. "Companies would have to decide what makes sense from a product (packaging) perspective," Soni said.

More: Those 'free' COVID tests you take? Labs are raking in millions in tax dollars, study says

The Biden administration has required private health insurers and Medicare to cover a monthly allotment of four boxes containing two tests apiece. The administration also has allowed Americans to order three rounds of home tests through the government-run website CovidTests.gov; the free test kits are delivered to a person's home address by the U.S. Postal Service.

Private insurers and Medicare must pay the cost of testing through the duration of the public health emergency, which has been extended through at least mid-October.

Officials with QuidelOrtho, which markets the QuickVue home COVID test, said the study shows serial testing is effective.

"The UMass study adds important data that will be closely examined," said Douglas Bryant, chairman and CEO of QuidelOrtho. "The key takeaway is that serial testing remains an effective tool for both symptomatic diagnosis and asymptomatic screening."

This article originally appeared on USA TODAY: COVID fears? FDA now says you need to pass 3 home tests to be safe


More Related News

'The tools are getting picked off': An ever-mutating mix of COVID variants means fewer and less effective treatments this fall

One up and coming variant renders society's last universal COVID antibody drug powerless, experts say. Another variant isn't far behind it.

'Blood on your hands' if world steps back on tackling COVID now - WHO official

LONDON (Reuters) -If rich nations think the pandemic is over, they should help lower-income countries reach that point too, a senior World Health Organization official told Reuters. In an interview, WHO senior adviser Bruce Aylward warned that richer nations must not step back from tackling COVID-19 as a global problem now, ahead of future potential waves of infection. In the last few weeks, WHO Director General Tedros Adhanom Ghebreyesus said the end of the pandemic was in sight, and U.S President Joe Biden said the pandemic was over.

Can You Get Your COVID Booster And 2022 Flu Shot At The Same Time?
Can You Get Your COVID Booster And 2022 Flu Shot At The Same Time?

Flu shots and the new bivalent COVID shots are now available. Here's what experts think about getting both during the same appointment.

U.S. FDA panel votes against Spectrum
U.S. FDA panel votes against Spectrum's lung cancer drug
  • US
  • 2022-09-22 17:03:34Z

The FDA panel voted 9 to 4 against the oral drug, poziotinib, citing marginal efficacy, high level of toxicities, and lack of dose optimization. The panel's...

Covid vaccination rates in US children under five lag despite effectiveness
Covid vaccination rates in US children under five lag despite effectiveness

Biden's recent announcement that the pandemic is ending could slow process further, as parents question the necessity of shots

Leave a Comment

Your email address will not be published. Required fields are marked with *

Cancel reply


Top News: Business