Nearly 60% of Americans show infection-related antibodies—meaning not antibodies produced by a vaccine—in their blood, per a survey by the CDC released Tuesday. That reflects the time period from December to February, reports the New York Times. But for children ages 11 and younger, that figure is even higher, with 75.2% of our nation's kids showing such antibodies in the same period. Older children, ages 12 to 17, showed nearly the same rate of infection as the younger set, with 74.2% of those kids exhibiting the antibodies. The omicron variant was apparently a big driver of infection across the country, as only about one-third of all Americans showed signs of a previous coronavirus infection before omicron arrived in December. Among children, that number hovered around 45% from September to December.
But though experts say the high rate of past infection "may offer at least a partial bulwark against future waves," per the Times, especially when it comes to serious illness that requires hospitalization, the news doesn't mean much in the way of herd immunity. "Having infection-induced antibodies does not necessarily mean you are protected against future infection," said Kristie Clarke, a co-author of the CDC study, per Reuters. "We did not look at whether people had a level of antibodies that provides protection against reinfection or severe disease." Experts are especially concerned about such repercussions as long COVID, a still-little-understood aftereffect of COVID in some patients. The CDC researchers note that getting vaccinated "remains the safest strategy for preventing complications from SARS-CoV-2 infection, including hospitalization among children and adults." (Read more COVID-19 stories.)