Post-infection immunity is superior to protection from COVID-19 vaccines, according to a new study from U.S. Centers for Disease Control and Prevention (CDC) researchers.
Natural immunity, or post infection immunity, provided 76 percent protection against COVID-19-associated hospitalisations while Omicron was the dominant virus strain in the country, the researchers found. A primary series of the Moderna or Pfizer vaccine, in people without a prior infection, provided just 39 percent protection.
Natural immunity also lasted longer at higher levels than both primary series of vaccination and vaccination with a messenger RNA booster on top of a primary series, according to the study. During Omicron predominance, natural immunity against hospitalisation was 74 percent 150 or more days after infection. A primary series without prior infection remained just 39 percent protective beyond 149 days, while three doses started at 81 percent protection but waned to just 31 percent after 150 or more days following the third dose.
The paper was published ahead of peer review by The Journal of Infectious Diseases. It was funded by the CDC. “Protection from COVID-19 mRNA vaccination and/or prior SARS-CoV-2 infection against COVID-19-associated hospitalisations … regardless of variant [was high],” Catherine Bozio of the CDC and the other researchers said. SARS-CoV-2 causes COVID-19.
The agency, which recommends a primary series and a bivalent booster for virtually all Americans 6 months of age and older, regardless of prior infection, did not respond to an email asking if the study’s findings would lead to a recommendation change.