Immunity to the Coronavirus May Persist for Years, Scientists Find

Important immune cells survive in the bone marrow of people who were infected with the virus or were inoculated against it, new research suggests.

Immunity to the coronavirus lasts at least a year, possibly a lifetime, improving over time especially after vaccination, according to two new studies. The findings may help put to rest lingering fears that protection against the virus will be short-lived. Together, the studies suggest that most people who have recovered from Covid-19 and who were later immunized will not need boosters. Vaccinated people who were never infected most likely will need the shots, however, as will a minority who were infected but did not produce a robust immune response. Both reports looked at people who had been exposed to the coronavirus about a year earlier. Cells that retain a memory of the virus persist in the bone marrow and may churn out antibodies whenever needed, according to one of the studies, published on Monday in the journal Nature.