Some rapid antigen tests may not be able to detect the omicron COVID-19 variant effectively enough, according to Anthony Fauci, M.D., director of the National Institute of Allergy and Infectious Diseases. “We’re getting preliminary information that not all of the [rapid] diagnostic tests will be accurate with omicron,” Dr. Fauci said in a virtual conversation with the Chamber of Commerce Foundation on Thursday.
That’s a problem, as rapid tests have been a significant—though imperfect—tool for detecting the SARS-CoV-2 virus. “Some, and many of the commonly used ones, appear to pick up and detect omicron quite well,” Dr. Fauci said. “We’re in the process of doing large screening to determine which of these antigen point-of-care rapid tests still maintain their accuracy of diagnosis. But clearly, there are some that do. We’re trying to find out those that don’t reflect an accurate result. And if we do, make sure that those tests are not used to diagnose omicron.”
Even at their best, rapid antigen tests haven’t been as accurate as polymerase chain reaction (PCR) tests, which are the gold standard for diagnosing COVID-19, as SELF has reported. According to a Cochrane review of 64 studies and more than 24,000 testing samples, rapid antigen tests managed to detect COVID-19 in 72% of symptomatic COVID-19 cases pre-omicron. In positive people without symptoms, they were only about 58% accurate. On the other hand, PCR tests are generally estimated to be around 98% accurate at detecting COVID-19 infections when used correctly. But rapid tests can come back in as little as 15 minutes at home, where PCR tests must be sent to a lab and take a few hours at minimum for results—and often take days.
Another major blow is that omicron has significantly reduced the effectiveness of monoclonal antibodies, one of few COVID-19 treatments. Monoclonal antibodies are lab-made antibodies delivered intravenously to high-risk people who have tested positive for COVID-19 or been in close contact with someone who has tested positive, per the U.S. Department of Health and Human Services. “When you look at…