Data on the efficacy of COVID-19 vaccines versus the delta variant of the coronavirus is limited, but early studies suggest that the vaccines provide protection against the variant, now the most commonly circulating strain in the U.S.
Five things to know:
- The delta variant has a much easier time evading the neutralizing antibodies produced by COVID-19 vaccines if a person has only gotten one shot, according to a study published in Nature.
- Pfizer's COVID-19 vaccine was 64 percent effective at preventing infection and symptomatic COVID-19 amid the spread of the delta variant in Israel. It was 93 percent effective at preventing serious illness.
- Both Johnson & Johnson's and Moderna's COVID-19 vaccines have proven to be effective against the delta variant in early studies. Johnson & Johnson's vaccine demonstrated "strong, persistent activity against the rapidly spreading delta variant and other highly prevalent SARS-CoV-2 viral variants" in an early study, and Moderna's vaccine produced neutralizing antibodies after two doses.
- Some experts believe people who were vaccinated with Johnson & Johnson's COVID-19 vaccine may need to get a booster shot of an mRNA vaccine from either Pfizer or Moderna to protect against the delta variant.
- Pfizer's and AstraZeneca's COVID-19 vaccines were both highly effective in preventing hospitalization from the delta variant in a study by Public Health England.