Nearly three-quarters of Americans have some Covid immunity, experts say

Almost three-quarters of Americans are now estimated to have some level of immunity to the Omicron Covid variant that created havoc after it emerged late last year just as people hoped the pandemic was finally waning.

About half of eligible Americans have received booster shots, there have been nearly 80m confirmed infections overall and many more infections have never been reported.

One influential model uses those factors and others to estimate that 73% of Americans are, for now, enjoying protection from Omicron, the dominant variant, and that could rise to 80% by mid-March, experts say.

This will prevent or shorten new illnesses in protected people and reduce the amount of virus circulating overall, probably tamping down new waves. Hospitals will get a break from overwhelmed ICUs, experts agree.

With varying degrees of relief and caution, many Americans are starting to return to their pre-pandemic lifestyles.

Sarah Rixen, 41, of Bismarck, North Dakota, started singing again with a civic chorus after taking a year off. Now, with Omicron winding down, she said she feels more confident than at any time since the crisis began.

As mask mandates ease, workers return to offices and flights fill up, experts are trying to understand whether this return to normal can last, or if another setback is looming.

To address that, researchers are using health data from other countries such as Britain, Denmark, South Africa and Qatar to project what could be in store.

Scientists at Johns Hopkins University Bloomberg School of Public Health estimate that about three out of four people in the US will have been infected by Omicron by the end of the surge.

They estimate about 45% of Virginians have the highest level of immunity through boosted vaccination or through vaccination plus a recent infection with Omicron.

Another 47% have immunity that has waned somewhat; and 7% are the most vulnerable because they were never vaccinated and never infected.