Testing people multiple times after they've recovered from COVID-19 may not be a useful practice, as these tests can be a "red herring," Michael Osterholm, PhD, a public health expert told STAT News.
Dr. Osterholm is director of the University of Minnesota's Center for Infectious Diseases Research and Policy in Minneapolis. He is among experts who doubt the value of using reverse transcription polymerase chain reaction testing on patients who have recovered from COVID-19 and continuing to test them until the test comes back negative.
There have been several cases worldwide where a person has continued to test positive for COVID-19 after recovery. For example, a mother tested positive for COVID-19 for 55 days after her baby was born at a hospital in Montreal, Canada. As a result, she was not able to hold or nurse her newborn for nearly two months.
Some studies are also now showing that some recovered COVID-19 patients, tested using polymerase chain reaction, will continue to test positive for long periods, STAT reported. Polymerase chain reaction tests can identify fragments of virus DNA, but it cannot determine if a person is shedding the whole virus that can be transmitted to other people and infect them, or if they are only shedding viral debris that is not infectious.
Health officials in South Korea studied 285 COVID-19 patients who recovered and later tested positive for the virus. They found these patients were not infectious and could not transmit the virus.
"It's is a red herring," said Dr. Osterholm about testing using reverse transcription polymerase chain reaction after COVID-19 recovery, according to STAT. "Because what it leads us to believe is something that very likely is not true, and that is that we're still shedding infectious virus."