Thread by @DrEricDing

Good news: Immunity to #COVID19 lasts at least a year, improving over time especially after vaccination.

Cautious news: Vaccinated who were never infected most likely will need [booster] shots, plus infected who did not produce a robust immune response.
nytimes.com/2021/05/26/hea…

2) 2 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 in the journal Nature.

3) The other study, posted online at BioRxiv, a site for biology research, found that these so-called memory B cells continue to mature and strengthen for at least 12 months after the initial infection.

4) “in fact, memory B cells produced in response to infection with SARS-CoV-2 and enhanced with vaccination are so potent that they thwart even variants of the virus, negating the need for boosters, according to Michel Nussenzweig, an immunologist at Rockefeller University”

5) ““People who were infected and get vaccinated really have a terrific response, a terrific set of antibodies, because they continue to evolve their antibodies,” Dr. Nussenzweig said. “I expect that they will last for a long time.”

6) The result may not apply to protection derived from vaccines alone, because immune memory is likely to be organized differently after immunization, compared with that following natural infection….

7) …That means people who have not had Covid-19 and have been immunized may eventually need a booster shot, Dr. Nussenzweig said. “That’s the kind of thing that we will know very, very soon,” he said.