Coronavirus Disease-19 and Re-infection: Unknown of the Unknown

Coronavirus disease has caused seven million infections worldwide, of which, 3.1 million individuals have recovered. Though, most individuals develop antibodies, whether these antibodies result in clinical improvement/immunity from future infection is not known. It is also not known about durability of antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). No human re-infection with SARS-CoV-2 has been confirmed to date, although a few case reports have mentioned patients who have tested positive again after recovery from the initial illness. Whether these cases represent a state of carrier or re-infection or reactivation, is not known. Nevertheless, the possibility of re-infection remains a matter of concern and yet another question about SARS-CoV-2 which is still unanswered.