Many thousands of Americans have been infected with the omicron strain of COVID-19 in the last month, including many who were vaccinated.
That’s no knock against the vaccines. They remain very effective at preventing severe disease and death, especially for those who have received three doses: an initial two plus a booster.
But most people — including hundreds of thousands in the Philadelphia area — have not gotten a booster. If they’ve recovered from an infection with omicron, can they skip the third shot? Now that cases are once again on the decline, are they good to go?
In the short term, probably yes, according to researchers who study the immune system.
Evidence suggests that the combination of vaccination plus infection — regardless of which came first — enhances the antibody response much like a booster shot.
“Hybrid” immunity is more of a layperson’s term, not found in scientific textbooks. The key is the number of exposures, whether it’s through three doses of the vaccine or two doses plus infection, Barker says.
“Basically if you’ve seen the virus three times, you have similar antibody levels,” she said. “But we don’t know about the longevity of those antibody responses.”
