Prevalence, durability of COVID-19 antibodies in unvaccinated

Editor's Note

This study led by Marty Makary, MD, MPH, and Dorry Segev, MD, PhD, at Johns Hopkins University School of Medicine, Baltimore, finds natural immunity in unvaccinated healthy US adults up to 20 months after testing positive for COVID-19.

Of 1,580 study participants, antibodies were detected in:

• 99% of individuals who reported a positive COVID-19 test result
• 55% of those who believed they had COVID-19 but were never tested
• 11% who believed they had never had COVID-19.

Antibodies were observed after a positive COVID-19 test result up to 20 months, extending the previous 6-month durability data.

The researchers note that although evidence of natural immunity up to 20 months after testing positive for COVID-19 is encouraging, it is unclear how this correlates with protection against future SARS-CoV-2 infections and emerging variants.