This study corroborates the earlier study by Long et al. in the Chinese population (doi: 10.1038/s41591-020-0965-6), which demonstrated that 40% of asymptomatic patients were seronegative for IgG at 8 weeks. The decline in protective antibody titre is quicker than that reported for SARS-CoV-1. Hence ‘immunity passport’ for infected COVID-19 patients is questionable. Also, duration of vaccine efficacy is a matter of concern and will have to be assessed meticulously; and addressed accordingly.
Article: Ibarrando FJ, Fulcher JA, Goodman-Meza D, et al. Rapid Decay of Anti-SARS-CoV-2 Antibodies in Persons with Mild Covid-19. N Engl J Med online publication ahead of print 21st July 2020 doi: 10.1056/NEJMc2025179Rapid Reduction of Anti-SARS-CoV-2 Antibodies after Mild Illness