The study showed the typical antibody response after an acute viral infection peaked between three and four weeks and then waned.
The authors studied the antibody response of 59 patients and 37 healthcare workers at Guy’s and St Thomas’ NHS Foundation Trust in London for three months following the onset of their symptoms.
Those with severe disease generated the strongest antibody response, and although this response diminished, neutralising antibodies were still detectable more than 60 days after symptoms began.
People with a milder COVID-19 disease also generated an immune response, but it was smaller and declined towards baseline levels.
Some healthcare workers had no detectable immune response within the same follow-up period.
The results suggest the kinetics of the response are similar to other endemic seasonal coronaviruses.
These insights have notable implications for vaccine design and disease management.
They suggest vaccines will need to generate a robust and long-lasting immune response akin to that generated in severely ill patients and that boosters may be required to provide long-lasting protection.
The authors say studies using samples collected from these same study participants at extended time points are now needed to determine the longevity of the neutralising antibody response as well as the neutralising antibody threshold for protection from reinfection.
Research shows those with an acute viral attack might be protected against reinfection for longer periods than those with milder symptoms.