Home COVID test kit
A home COVID-19 test kit. Courtesy NIH

As the pandemic continues, the Food and Drug Administration has granted extensions to the shelf life of some at-home rapid antigen tests, causing confusion about whether a test is safe to use.

If you find a box of tests that says they’re expired, are they really past their prime? Not necessarily, says Dr. Eli Aronoff-Spencer is an assistant professor of medicine at UC San Diego and co-leads a NIH grant to develop and commercialize new tests. 

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At-home COVID rapid tests are similar to other tests previously on the market, such as pregnancy tests. They work because of chemical reactions that occur with antigens, proteins found in the coronavirus. 

It’s important to remember that while the technology of these test kits is not new, the virus is. When test makers took their products to market, they had limited data to show how long they last. 

“So when the [Food and Drug Administration] says ‘How long does the test kit last?’ what they’re really saying is ‘How long did the test kit get tested for?’” said Aronoff-Spencer. 

“Just like we know milk that’s gone past its spoil date sometimes isn’t spoiled,” he said. “That’s almost certainly the case here.” 

The materials in the test kits can degrade, making them less reliable. “It’s usually water, oxygen and heat that are the three biggest enemies,” Aronoff-Spencer said. 

But with more time, companies have been able to show that their tests work beyond the printed expiration dates, so it’s worth checking the FDA’s website before throwing them out. The agency has granted extensions for some tests — not all — and you can find an updated expiration date for the brand you have at home. 

If you find that the test has indeed expired — or if they’ve been stored for a long time in a hot environment, such as your car — the FDA recommends using a different one. 

Read the full article on inewsource.org.

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