Scientists Explain COVID-19 Re-infection
November 30, 2020
A large number of people continue to get infected with COVID-19 and so do a large number of patients recover. In some cases, people are testing positive for SARS-CoV-2 again or are experiencing a recurrence of clinical symptoms. Some scientists believe that a positive retest is due to the long-term persistence of the virus in the body. Some studies attribute re-infection to false-negative RT-PCR results, long term viral shedding and increased viral replication due to drug discontinuation.
It is necessary to differentiate between prolonged viral shedding or reactivation and true re-infection. Viral shedding in the upper respiratory tract may also take as long as 83 days. If a person tests positive after this period, it could be confirmed as a re-infection. A true infection should be detected by isolation of the complete viral genome and not just fragments. The GI tract may also act as a reservoir for SARS-CoV-2 even if samples from the upper respiratory tract come out negative. Hence stool samples should also be tested at the time of discharge. Some researchers believe that retesting positive for COVID-19 may be explained by the infection’s reactivation or relapse.