antibody study indicates More than half of the U.S. has had COVID-19

Following the record surge in COVID-19 cases during the Omicron-driven wave, some 58 percent of the U.S. population overall and more than 75 percent of younger children have been infected with the coronavirus since the start of the pandemic, according to a U.S. nationwide blood survey released on Tuesday.

The study of blood samples sent to laboratories between December and February – when Omicron cases were raging – showed children, many of whom remain unvaccinated, had the highest rates of infection during that surge, while people 65 and older – a heavily vaccinated population – had the lowest.

Scientists looked for specific antibodies produced in response to the SARS-CoV-2 virus that is only present after infection and is not generated by COVID-19 vaccines.

In children aged 11 and younger, 75.2 percent were positive for infection-related antibodies from December to February, up from 44.2 percent in the prior three-month period.

In children aged 12-17, 74.2 percent carried antibodies, up from 45.6 percent between September and December. The overall rate was 33.5 percent for the entire population during that earlier period.

“Having infection-induced antibodies does not necessarily mean you are protected against future infection,” said Kristie Clarke of the U.S Centers for Disease Control and Prevention (CDC) during a media briefing to discuss the data.

“We did not look at whether people had a level of antibodies that protects against reinfection or severe disease.”

Samples were collected from commercial laboratories testing blood for reasons unrelated to COVID-19, such as routine medical care.

Traditional methods of disease surveillance do not capture all COVID-19 cases because some are asymptomatic, not diagnosed, or not reported, the CDC said.

The median sample size per four-week period was 73,869 collected between September and January. That fell to 45,810 in February.

Overall, U.S. COVID-19 infections have reached 80.8 million, with a 22.7 percent increase over the last week, and hospital admissions rose 6.6 percent from the prior week.

While deaths fell 13.2 per cent per cent, week-over-week, the United States is fast approaching the grim milestone of 1 million total COVID-related deaths.

More than 66 per cent of the U.S. population is considered to be fully vaccinated against COVID-19, according to federal data. Nearly 46 per cent of those Americans had so far also received a booster dose.