Dynamics of viral load and anti-SARS-CoV-2 antibodies in patients with positive RT-PCR results after recovery from COVID-19.

The recent rise in the number of coronavirus disease 2019 (COVID-19) patients tested as reverse transcription polymerase chain reaction (RT-PCR) positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) after recovery has caused dilemma regarding the medical measures and polices. We evaluated the dynamics of viral load and anti-SARS-CoV-2 antibodies in 4 patients with positive RT-PCR results after recovery. In all patients, IgG and IgM antibodies reached their maximum about a month after the onset of initial symptoms. Then, IgG titers plateaued, and IgM titers decreased regardless of RT-PCR results. The IgG and IgM antibodies did not rise after the positive-negative positive RT-PCR results in any of the patients. Our results reinforced that the post-negative positive RT-PCR results may be due to detection of RNA particles rather than re-infection or recurrence in individuals who have recovered from COVID-19.