By Amy Orciari Herman
Edited by
– David G. Fairchild, MD, MPH, and
– Jaye Elizabeth Hefner, MD

Check out some of the latest COVID-19 news:

Reinfection risk: A study in the Lancet Respiratory Medicine helps characterize the risk for SARS-CoV-2 reinfection in a close contact setting. Researchers studied roughly 3000 Marine recruits (mostly young males) who had negative PCR results for SARS-CoV-2 for 3 weeks in a row during a supervised quarantine, after which they were transferred to a military training site. Less than 10% were seropositive for SARS-CoV-2 at baseline. During 6 weeks’ follow-up at the training site, 10% of the seropositive group and 48% of the seronegative group had at least one positive PCR result. In the seropositive group, those who became infected had lower antibody levels at baseline than those who did not become infected; they were also more likely to test negative for neutralizing antibody activity at baseline. Commentators note, “These data confirm that seropositive individuals have an important, albeit limited, protection for new infections.” They add that COVID-19 does not seem to offer “an almost universal and long-lasting protective immunity, [like] that seen in measles, for example.”

Bamlanivimab authorization revoked: The FDA has revoked the emergency use authorization for the monoclonal antibody bamlanivimab as a monotherapy for COVID-19. The agency granted the EUA in November 2020, authorizing the treatment for outpatients with mild-to-moderate illness who were at increased risk for disease progression. Now, the FDA says that “the known and potential benefits of bamlanivimab, when administered alone, no longer outweigh the known and potential risks for its authorized use.” The change follows emerging data showing that SARS-CoV-2 variants have a high rate of resistance to the antibody as monotherapy. Bamlanivimab is still authorized for use when given with etesevimab.

The Lancet Respiratory Medicine article (Free)
The Lancet Respiratory Medicine comment (Free)
FDA news release (Free)
NEJM Journal Watch COVID-19 page (Free)
NEJM COVID-19 page (Free)