CVS and Walgreens are selling out of at-home COVID tests—here’s what you need to know about getting an accurate result
Finding out whether you have COVID-19 is no longer as difficult as it was this time last year, when you likely had to visit a health care facility or city-run testing site, and wait up to a week for results.
This holiday season, many retailers, including chains like CVS and Walgreens, superstores like Walmart, and local family-owned pharmacies, sell rapid antigen tests, such as QuickVue, Ellume and BinaxNOW, which offer results in fifteen minutes. The tests, which don’t require a prescription or the filling out of any forms, can be easily taken from home—if you manage to find one in stock.
Amid the recent surge of the highly contagious omicron variant, especially in the Northeast and Midwest regions, demand for rapid tests have gone through the roof, with many people waiting hours in long lines at testing sites to receive one. This week has been especially crazy, as millions of people hope to test negative before traveling home to see family.
Rapid tests, while not perfect, are still an important public health tool, and can be quite accurate when used correctly.
Prices for BinaxNOW and other rapid tests start at about $7 per test, though in areas of extreme demand, like New York, that price tag has risen to around $25 or up to $45. By January 2022, President Biden has said, the government will begin sending out rapid tests for free.
Can I get a rapid test near me?
Some cities, like New York, have set up testing tents or vans on street corners to meet explosive demand for tests. The turnaround time for PCR tests at these sites can vary anywhere from 24 hours to five days, leading customers back to drug stores for rapid tests, where boxes are flying off shelves.
Some retailers, in an effort to maintain inventory, have instated a per-customer limit. This week, Walgreens announced it would be limiting customers to four test boxes each, while CVS limited to six, and Amazon, where tests are in and out of stock, limited to ten.
Stores including Walgreens, CVS, Rite Aid and Walmart all offer up-to-date inventory information on their respective websites, where customers can find the closest chain location with rapid tests in-stock, or potentially order boxes online.
Rapid test vs. PCRs
Rapid tests are useful in a different way than polymerase chain reaction (PCR) tests, which are done in a clinical setting and sent to a lab. For one thing, rapid test results come in minutes; PCR tests can take days, and require lining up at testing site or healthcare facility with other potentially ill people.
Where PCR has rapid tests beat: they make many copies of the virus’s genetic material, allowing it to detect even the smallest traces of the virus. Rapid tests, on the other hand, don’t amplify the virus, making them less sensitive.
If a rapid test is taken too soon after infection, the virus may not yet be widely replicated, meaning the test won’t pick it up and will show a false negative. This means rapid tests are best used for those with symptoms; their real-world performance is “generally lower” than PCRs, according to the CDC.
The best way to use rapid tests is to take one every three days, which will ensure you catch different viral load levels. Using rapid tests this way will catch 98% of infections, according to the NIH, putting them on par with what they call “the gold standard”: PCRs.
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