New Study Finds ‘Neutralizing’ COVID-19 Antibodies Decline Significantly After a Month

A new study from China’s Nanjing University has found that “neutralizing” antibodies in the serum of recovered COVID-19 patients decline sharply within a month of hospital discharge. However, the study, published in PLOS Pathogens, doesn’t conclude that the decline necessarily means immunity wanes in one month. In the study of 26 COVID-19 patients, the researchers found that 80.7 percent of patients had some level of antibodies, the same ones whose presence in convalescent plasma patients resulted in clinical improvement. Of this, only a small portion had a “potent level” of neutralization activity, which the study’s researchers say highlights the significance of carefully selecting patients from which to select serum for use in experimental convalescent plasma therapy. “Studies like this are a vital part of the ‘work-in-progress’ to make sense of who has immunity and how long for,” said Imperial College immunologist Danny Altmann, who was not involved in the study.