Natural immunity better protects against the Delta strain of COVID-19 than a vaccine, according to a study released by the Centers for Disease Control and Prevention (CDC) on Wednesday.
Researchers examined COVID-19 cases and hospitalizations from May through November 2021 in California and New York. The research team examined case and hospitalization rates among four cohorts of people: the unvaccinated and previously uninfected, the vaccinated and previously infected, the unvaccinated with a previous COVID-19 diagnosis, and the vaccinated with a previous COVID-19 diagnosis.
The study found that the natural immunity obtained through recovering from a bout of COVID-19 gave people a much greater degree of protection against the Delta strain of COVID-19 than receiving a COVID-19 vaccine. The study said:
By the week beginning October 3, compared with COVID-19 cases rates among unvaccinated persons without a previous COVID-19 diagnosis, case rates among vaccinated persons without a previous COVID-19 diagnosis were 6.2-fold (California) and 4.5-fold (New York) lower; rates were substantially lower among both groups with previous COVID-19 diagnoses, including 29.0-fold (California) and 14.7-fold lower (New York) among unvaccinated persons with a previous diagnosis, and 32.5-fold (California) and 19.8-fold lower (New York) among vaccinated persons with a previous diagnosis of COVID-19. During the same period, compared with hospitalization rates among unvaccinated persons without a previous COVID-19 diagnosis, hospitalization rates in California followed a similar pattern. These results demonstrate that vaccination protects against COVID-19 and related hospitalization, and that surviving a previous infection protects against a reinfection and related hospitalization. Importantly, infection-derived protection was higher after the Delta variant became predominant, a time when vaccine-induced immunity for many persons declined because of immune evasion and immunologic waning (2,5,6).
The researchers urged caution in drawing conclusions from the study, noting that the vaccine afforded people better protection from COVID-19 variants prior to Delta. The researchers said that the degree of immunity offered by previous infection and by the vaccine is likely to change with the spread of new variants, such as Omicron. The researchers still pushed vaccines as “the safest strategy” for combating COVID-19.
“Although the epidemiology of COVID-19 might change as new variants emerge, vaccination remains the safest strategy for averting future SARS-CoV-2 infections, hospitalizations, long-term sequelae, and death. Primary vaccination, additional doses, and booster doses are recommended for all eligible persons. Additional future recommendations for vaccine doses might be warranted as the virus and immunity levels change,” the study said.
The Biden administration has continued to push COVID-19 vaccines in its rhetoric and through executive action while downplaying and ignoring the protection offered by natural immunity. Earlier this month, the CDC began emphasizing “up to date” vaccinations over “fully vaccinated,” signaling a shift toward emphasizing booster shots in addition to the original vaccine dose.
Dr. Marty Makary of Johns Hopkins University slammed the CDC over the move. “Well CDC just did it, as I predicted. They changed their language from ‘Get a booster’ to ‘Are you up to date?’ This manipulation [of] words implies that low-risk people without a booster are out-of-date. Also sets the stage for [frequent] boosters[.] Covid vaccinations are not software.”