With both infection and vaccination, the immune system gets quicker, stronger and smarter after being exposed to a new challenge. Researchers have found that people who were infected by Covid-19 and later vaccinated crank out higher levels and a broader array of antibodies that last longer than do people who have only been vaccinated.

Similarly, a study last month by the Oregon Health and Science University found that vaccinated people who experienced breakthrough infections produced higher levels of antibodies that were up to 1,000% more effective than those generated two weeks after a second dose of the Pfizer vaccine. The researchers described this as superimmunity.

“I think this speaks to an eventual end game,” said co-author Marcel Curlin. “It doesn’t mean we’re at the end of the pandemic, but it points to where we’re likely to land: Once you’re vaccinated and then exposed to the virus, you’re probably going to be reasonably well-protected from future variants.” Dr. Curlin added: “Our study implies that the long-term outcome is going to be a tapering off of the severity of the worldwide epidemic.”