Two doses of Pfizer, AstraZeneca effective against Delta variant
Two doses of Pfizer or AstraZeneca’s COVID-19 vaccine are nearly as effective against the highly transmissible Delta coronavirus variant as they are against the previously dominant Alpha variant, a study published on Wednesday showed.
Officials say vaccines are highly effective against the Delta variant, now the dominant variant worldwide, though the study reiterated that one shot of the vaccines is not enough for high protection.
The study, published in the New England Journal of Medicine, confirms headline findings given by Public Health England in May about the efficacy of COVID-19 vaccines made by Pfizer-BioNTech and Oxford-AstraZeneca, based on real-world data.
Wednesday’s study found that two doses of Pfizer’s shot was 88 percent effective at preventing symptomatic disease from the Delta variant, compared to 93.7 percent against the Alpha variant, broadly the same as previously reported.
Two shots of AstraZeneca vaccine were 67 percent effective against the Delta variant, up from 60 percent originally reported, and 74.5 percent effective against the Alpha variant, compared to an original estimate of 66 percent effectiveness.