Study finds lasting protection in patients who have recovered from COVID-19

Editor's Note

This study led by researchers at the Massachusetts General Hospital and Harvard Medical School, Boston, finds that patients who survive serious COVID-19 infections have a long-lasting immune response against the virus.

The study includes a cohort of case patients with known COVID-19 infection (343) and controls (1,548). Blood samples were drawn up to 4 months after a patient began showing symptoms, and they were compared with blood samples from patients obtained before the pandemic.

The researchers found that antibodies against the receptor binding domain (RBD) of the virus spike protein were accurate indicators of a recent severe COVID-19 infection, and that the presence of immunoglobulin G (IgG) antibodies targeting the RBD region was a highly sensitive marker of infection 14 days from onset of illness.

The levels of IgG remained elevated in infected patients for 4 months and were associated with the presence of protective neutralizing antibodies.

The findings show that key antibody responses to COVID-19 do persist for 4 months, which means that patients are very likely protected for that period of time, the researchers say.