Some households in Metro Detroit have started receiving the government’s four free COVID-19 tests being sent out to those who ordered them.
They are generating several questions being sent in to Dr. Frank McGeorge. Several weeks ago a viewer asked if the home antigen tests would be able to detect the omicron variant. At the time there was very little data, and because the tests look for a different part of the virus than the spike, it was estimated they should be just as accurate.
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Currently, studies are being done and the better answer is that, according to the FDA, early data suggests that antigen tests do detect the omicron variant, but may have reduced sensitivity.
Randy asks: We have ordered the free COVID tests to be delivered by USPS within a couple of weeks. Our mailbox is in the cold and we don’t get to it often. Will it harm the tests if they are exposed to the cold or freeze?
Lots of people have the same question. The at-home rapid antigen tests all have similar storage and use temperature requirements. For example, a Flowflex antigen home test should be stored and used between 36 degrees and 86 degrees Fahrenheit. While an Abbot Binax Now test has a storage requirement between 35.6 and 86 degrees Fahrenheit.
Obviously with the bitter cold, Michigan has been experiencing, you can imagine anything being delivered by the USPS in Michigan has the potential to get exposed to temperatures below 35 degrees. The question is: What’s the effect?
The concern is that these tests use a chemical liquid to extract the viral particles from the swab and its effectiveness could be altered if it were to become extremely cold or even frozen.
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While this is an important question, the fact is this hasn’t been clinically tested. The Emergency Use Authorization is for the tests to be maintained and used within the required temperatures.
Most experts think that if this liquid were to become very cold or freeze for more than a range of a couple of hours to even two days, it should be OK. The most important thing is that the test needs to be returned gradually to normal room temperature before it is used.
There is one study that shows if some of these tests are used at temperatures above the recommended range, they are more likely to be incorrectly negative. The same study also found when some rapid antigen tests were used in very cold conditions they had more incorrectly positive results. So, the temperatures they’re used at does matter.
Read: Complete Michigan COVID coverage