Antibodies will wane over time but memory B cells are long-lasting.

A large body of research on the coronavirus now indicates that both natural infection and vaccines stimulate the production of these long-lasting memory cells, which means that boosters should not be needed any time soon to conquer covid-19. We already knew mRNA vaccines — like the Moderna and Pfizer vaccines being widely administered against the coronavirus — form memory B cells. That finding was bolstered in a big way Monday, when researchers reported finding memory B cells in the bone marrow of people who had experienced even mild cases of covid-19. Another study of recovered covid-19 patients found the development of memory T cells comparable to those generated by yellow fever vaccination, which usually needs just one dose over a person’s lifetime. And a 2020 study showed that T cells generated among patients who survived the SARS pandemic of 2003, which is caused by a similar virus, were still going strong 17 years later, indicating long-lasting immunity.