CDC: Prior infection more protective for delta

Vaccinated Americans with prior COVID-19 infections had the highest protection against hospitalization and reinfection from the delta variant, according to a new study the Centers for Disease Control and Prevention (CDC) released Wednesday.

The study found protection against reinfection and hospitalization grew significantly among both unvaccinated and vaccinated individuals who had previously recovered from COVID-19, in the time period before the delta variant emerged to after it became the dominant strain in the U.S.

Prior infection provided better protection than vaccination alone, the study found.

The study is likely to further fuel the people who insist natural immunity is just as protective and  who won’t get vaccinated because they’ve been infected with COVID-19 at some point.

Major caveats: While the study period ranged from the time before delta took over to when it was the dominant variant, data ends in November, before omicron took over. The CDC also noted that the analysis did not include information on the severity of initial infection, and does not reflect the risk of severe disease or death from a COVID-19 infection.

CDC conclusion: “We know that vaccination remains the safest strategy for protecting against Covid-19,” said Benjamin Silk, a CDC epidemiologist and one of the authors.