There are studies showing that some people have “superhuman immunity” to fight COVID-19 if they have previously had the virus and received two doses of vaccine.
The researchers say people who have had “hybrid” exposure to COVID-19, including infection and then full vaccination, have had a potent immune response to the virus and are likely to be able to fight most variants.
A Rockefeller University study published last month found that antibodies in people who had hybrid exposure were very high and could neutralize six variants, including Delta.
“Those people have amazing responses to the vaccine,” Rockefeller University virologist Theodora Hatziioannou, who helped lead the study, told NPR.
“After natural infections, antibodies seem to evolve and become not only more potent, but also broader. They become more resistant to mutations within the [virus]”.
Hatziioannou said it was unclear whether all people who had COVID-19 and were vaccinated would have such a strong immune response.
The Rockefeller study included data on 14 patients.
“With all the patients we studied, we saw the same thing,” Hatziioannou said.
The virologist said it had not yet been determined whether people receiving a COVID-19 booster injection could develop the same immune response as those with hybrid exposure.
“I’m pretty sure a third shot will help a person’s antibodies evolve even more, and maybe they’ll gain some breadth. [or flexibility], but if they will ever manage to get the amplitude seen after the natural infection, it is not clear, “he said.
University of Pennsylvania immunologist John Wherry told NPR that his own research, published online last month, has shown that people who have been fully vaccinated are also developing flexible antibodies.
“In our research, we already see that this evolution of antibodies happens in people who are only vaccinated, although it probably happens more quickly in infected people,” he said.