Study finds previous COVID-19 infection, but not vaccination, improves performance of antibodies and potentially provides longer-term protection

New research to be presented at this year’s European Congress of Clinical Microbiology & Infectious Diseases (ECCMID 2022, Lisbon, 23-26 April) shows that, although over time the number of SARS-CoV-2 antibodies falls in both previously infected and vaccinated patients, the performance of antibodies improves only after previous infection (and not vaccination). This difference could explain why previously infected patients appear to be better protected against a new infection than those who have only been vaccinated. The study, by Dr Carmit Cohen of the Sheba Medical Center, Ramat Gan, Israel, and colleagues, also found that, contrary to expectations, previously infected patients with obesity had a higher and more sustained immune response than overweight and normal weight range patients. While protection against re-infection lasts for a long time in SARS-CoV-2 recovered patients, breakthrough infections are increasingly common six months after vaccination. In this study the authors analysed the humoral (antibody-induced) immune response in COVID-19...