SOME COVID TEST KITS GET EXPANDED LIFE

Americans were recently offered another chance to order free at-home coronavirus testing kits through the Postal Service. But since federal and state agencies have extended the shelf lives of several brands of tests, it may not always be clear when the free kits, and others purchased separately, will expire.

Although each box has an expiration date, meant to indicate when the test inside will no longer provide a reliable result, the Food and Drug Administration has given emergency authorization for shelf-life extensions of several testing kits as their manufacturers gather more data. Some states have also received FDA extensions for batches of expired laboratory tests or have endorsed their own extensions for at-home tests authorized by federal regulators. This means that some tests that are set to expire in the coming weeks may actually be usable for several more months.

In January, the FDA granted a request from Florida to lengthen by three months the life span of laboratory rapid tests that had expired. In March, California’s Public Health Department approved the emergency use of at-home test kits beyond their FDA-authorized expiration dates. The blanket extension applied to all over-the-counter tests authorized by the FDA as long as each test’s control line — the line that is typically next to the letter C — is easily visible when the test is complete.

Some health departments have posted notifications on their websites when a manufacturer is granted an extension for its tests. But officials should not assume that everyone has access to the Internet or is comfortable enough using a computer to find that information, said Cindy A. Prins, a public health researcher at the University of Florida.

“I think that some people have gotten the message that there are COVID tests that can be used beyond the expiration date that’s printed on the test box, but they may not be aware that it’s not true of all COVID tests,” she said.

If a test kit has not received an authorized extension from the FDA and the box says it has expired, some public health researchers say that it can still be used under certain conditions. Most tests remain effective for some time if they are properly stored, Prins said.

Annette Regan, a public health researcher at the University of San Francisco, said that if the control line on a completed test is not visible, the test should not be considered valid, regardless of its result.