If you’re expecting at-home COVID-19 antigen tests in the mail, try to make sure you’re around when they arrive — or there could be problems.
With hundreds of millions of free at-home COVID tests available to order through a recently launched White House initiative, the U.S. Postal Service is delivering the FDA-approved kits to mailboxes across the country, McClatchy News reported.
But in the dead of winter, it’s important not to let those tests sit outside in the mailbox for too long, experts say.
“The sensitivity and specificity of the test can drop and vary depending on what temperature it’s in,” Dr. Asha Shajahan, a Michigan physician and medical director of Community Health at Beaumont Health Dearborn, told TV station WXYZ. “The best way to avoid that is to bring the test in as soon as you can.”
President Joe Biden’s administration is buying 1 billion coronavirus antigen tests from a variety of manufacturers, and most tests — such as the popular iHealth test — must be stored at a temperature between 36 and 86 degrees Fahrenheit.
Antigen tests exposed to temperatures above or below the 36-86 degree sweet spot for extended periods of time can deliver inaccurate results, according to a study published by the National Institutes of Health.
“Consequences may include false-negative test results,” the researchers wrote. “Storage and operation of [antigen tests] at recommended conditions is essential for successful usage during the pandemic.”
But if you can’t get to your mailbox for a few hours, that’s probably OK. These tests are generally able to withstand the elements, up to a point, according to Shajahan.
“What most of the companies are saying is that it’s OK if the test is left beyond those temperatures I mentioned for just a few hours,” she told WXYZ. “The maximum is 24 hours.”
Some manufacturers claim their product can be outside the 36-86 degree window for even longer, WUSA reported.
“If the test is stored outside the temperature range for a relatively short period of time — for a couple of hours up to a day or two — it will be fine to use,” a spokesperson for BinaxNOW told the outlet.
The spokesperson added that it’s important the “test and its components are used at room temperature.”
The iHealth test echoes that statement, with the user manual recommending that all pieces of the kit be at least 65 degrees Fahrenheit before use, and up to 86 degrees max.
Orders are limited to one shipment of four tests per household, McClatchy News reported. There is no way to select or request a specific brand of test, but all are approved by the FDA for at-home use.
To order free COVID testing kits, visit covidtests.gov