CDC says at least 58% of the US population has natural antibodies from a previous Covid infection
Blood is drawn by a registered nurse to test for antibodies to the coronavirus, June 16, 2020 in Washington, DC.
Win McNamee | beautiful pictures
Three in five people in the US now have antibodies from a previous Covid-19 infection with an even higher percentage of children, demonstrating how widespread the virus was during the winter omicron spike, according to the data. from the Centers for Disease Control and Prevention.
The proportion of people with natural Covid antibodies has increased dramatically from about 34% of the population in December to about 58% in February in an unprecedented wave of infections caused by the highly contagious omicron variant. The CDC analysis found no factors in those who had antibodies from vaccination.
The CDC released the data in its Mortality and Mortality Weekly Report on Tuesday.
The increase in antibody rates was most pronounced in children, indicating a high rate of infection in children during winter omicron episodes. About 75% of children and adolescents now have antibodies from past Covid infections, up from 45% in December.
The high infection rate in children is likely due to lower vaccination rates compared to adults. Only 28% of children 5 to 11 years old and 59% of adolescents 12 to 17 years of age were fully immunized as of April. Children under 5 years old are not eligible for vaccination.
The CDC analyzed approximately 74,000 blood samples each month from September to January from a national network of commercial laboratories. The sample size dropped to about 46,000 blood samples in February. The CDC tested samples for a specific type of antibody produced in response to a Covid infection, not a vaccination.
CDC officials told reporters on a call Wednesday that the study did not measure whether people with previous infections had high enough antibody levels to protect against reinfection and severe illness. Still, CDC Director Dr. Rochelle Walensky said health officials believe there is a great deal of protection in communities around the country from vaccination, booster and infection together, and warn Report that vaccination is the safest strategy to protect yourself against the virus.
“Those who have detectable antibodies from previous infection, we continue to encourage them to get vaccinated,” Walensky told reporters on a call. “We don’t know when that infection started. We don’t know if that protection has waned. We don’t know more about that level of protection than we do about the protection we offer. get from both vaccines and boosters.”
Scientists in Qatar affiliated with Cornell University found that natural infection provides about 73% protection from hospitalization if a person is reinfected with BA.2. However, three doses of Pfizer vaccine provided much higher protection against hospitalization with 98%. The study, published in March, did not undergo peer review.
Infections and hospitalizations have fallen by more than 90% from the peak of the omicron wave in January as infections in the US spiked to an average of more than 800,000 a day. New cases are increasing again due to the subvariable BA.2. Another secondary variable, BA.2.12.1, is now taking over in the US, accounting for about 29% of new infections, according to CDC data. Walensky said public health authorities believe BA.2.12.1 spreads about 25% faster than BA.2. However, she said the CDC does not expect to see more severe illness from BA.2.12.1 ., although studies are underway.
More than 98% of the US population lives in areas where they don’t need to wear masks indoors according to CDC guidelines due to low community levels of Covid, which takes into account both infections and hospitalizations. A US district judge last week denied the CDC’s requirement to wear a mask for public transportation, though the Justice Department filed an appeal. Walensky said the CDC continues to recommend that people wear masks on public transportation.
