This Is the Type of COVID-19 Test You Should Be Asking For
COVID-19 testing has changed since the outbreak began—and this one test is clearly the most reliable.
More than 45 million coronavirus tests have been administered in the U.S since the pandemic began, according to the most recent estimates by the Centers for Disease Control and Prevention (CDC). But depending on which report you are reading, anywhere from 5 to 20 percent of COVID test results could in fact be inaccurate. Now, we have some insight as to which testing methodology is most reliable, and which you may want to avoid. There are four basic COVID testing methods used by health care professionals to collect samples via swabs: nasopharyngeal (deep nasal collection), throat, nostril, and saliva. And as two top doctors told Today, one test is more accurate than the rest and that's the deep nasal swab.
Jake Deutsch, MD, clinical director and co-founder of Cure Urgent Care in New York City, and Eric Cioe-Pena, MD, an emergency medicine physician at Northwell Health in New York City, both told Today that the deep nasal swab is the most accurate COVID test. "There's not a lot of convincing data the other swab types are as good," Cioe-Pena said.
The CDC also recommends nasopharyngeal swabs. So, why is that testing method better than the throat, nostril, or saliva tests? Well, "because in most patients, the nasopharynx, or the space above the soft palate at the back of the nose, appears to have the highest concentration of virus," according to ARUP Laboratories in Salt Lake City, Utah.
Equally important as the testing method, however, is the manner in which samples are processed. There are two options, the most common of which is the molecular test, AKA the "polymerase chain reaction" (PCR) test. This kind of test "detects viral genetic code that does not exist in the human body otherwise," according to Cioe-Pena. "They're sensitive to the point where it will even detect fragments," which means that a test could still comeback positive for someone who had been sick but then recovered. According to the Food and Drug Administration (FDA), the PCR method is "typically highly accurate."
The other manner in which samples are processed is a rapid antigen test, which is usually done on-site and provides a much faster result, per the FDA. These tests didn't start getting approved by the FDA until mid-May and are the kind of testing kits that reveal results in 10 to 20 minutes. Antigen tests rely on a nasal or throat swab, but instead of looking for virus proteins in genetic material, they looks for them in the body.
But it turns out the latter is not quite as accurate. With the antigen tests, "positive results are usually highly accurate but negative results may need to be confirmed with a molecular test," the FDA warns. According to Cioe-Pena, the PCR tests boast 99 percent accuracy. By comparison, the antigen tests are about 93 percent accurate, according to Deutsch.
So, if you want to get the most reliable test results, then be sure to have a PCR deep nasal test done. You can be 99 percent confident that the results are accurate. And for more on COVID testing, check out 80 Percent of People Who Test Positive for COVID Have This in Common.