What to tell patients about expiry dates on at-home rapid COVID-19 tests

Many at-home rapid COVID-19 antigen tests kits may still be effective despite the expiry date on the box. Health Canada has extended the shelf life of some of the test kits after reviewing stability tests. Most kits have both the manufacture date and the expiry date on the box. While the kits were initially approved for a certain shelf life, Health Canada has extended the shelf lives of some kits based on tests performed by either the manufacturers or the National Microbiology Laboratory. This means the tests are valid up to 16 or 24 months (depending on the product) after the manufacturer date, which is often beyond the expiry date printed on the box. How do patients find out the real expiry date of the boxes of COVID-19 test kits sitting in their cupboards? The first step is to find the manufacture date. This might be listed as MFG or another abbreviation. Then, make sure you know how the dates are displayed. Health Canada requires medical device manufacturers to display dates in the YYYY-MM-DD format, so 2022-03-02 is March 2, 2022. Then, find if that test kit has the shelf life extended by Health Canada. Most provinces have a website about rapid antigen tests that lists the expiry date extensions. For example, Ontario Health has a list of all the rapid test kits with shelf life extensions and links to letters from the manufacturers showing the new expiry dates. The U.S. Food and Drug Administration also extended the expiry dates on some at-home rapid COVID-19 diagnostic tests and their information is easier to find with tables of specific lot numbers and new expiry dates. If there’s been an extension approved by Health Canada, calculate the new expiry date. For example, Health Canada extended the Abbot PanBio Nasal COVID-19 Rapid Test Device shelf life to 24 months. Patients can disregard the initial expiration date, and add 24 months to the manufacture date, as explained with photos on the B.C. Centre for Disease Control website. Another example is the Arton COVID-19 Antigen Test, which has the shelf life expanded by six months. The concern with expired tests is that they may give false negatives. A positive result on a COVID-19 test depends on the SARS-CoV-2 antigen in the nasal swab sample interacting with the labelled antibodies in the test kit, causing a colour change in the kit. But as the antibodies in the test kit degrade with time, they may not interact with the antigen to indicate a positive result even if the person giving the sample is sick, explained Dr. Christopher Labos, a Montreal physician in an Oct. 10 opinion piece for the Montreal Gazette. Rapid tests are still available for free in many parts of Canada. Instead of worrying if the tests in the cupboard are still valid, patients should pick up another box, just to be sure, Dr. Labos wrote. Remember to remind patients that rapid COVID-19 tests should be repeated a few times to confirm a negative test result. Also, make sure patients know to take the old test kits back to the pharmacy for proper disposal. Read: The same arm is better than switching when it comes to COVID-19 boosters

What to tell patients about expiry dates on at-home rapid COVID-19 tests

Register for free access or login.

Related Topics