Double dose of Pfizer, AstraZeneca vaccines ‘effective’ against Delta variant: Study

Two doses of BioNTech-Pfizer or Oxford-AstraZeneca's COVID vaccine are highly effective against the delta variant, a study published in the New England Journal of Medicine has found.

The BioNTech-Pfizer shots were 88% effective at preventing symptomatic disease, as compared to 93.7% against the alpha variant. The study reiterated the importance of taking both of the shots to achieve immunity.

Two shots of AstraZeneca vaccine were 67% effective against the delta variant, up from 60% originally reported, and 74.5% effective against the alpha variant.

"Only modest differences in vaccine effectiveness were noted with the delta variant as compared with the alpha variant after the receipt of two vaccine doses," researchers wrote in the study.

Scientists had previously noted that a single dose of either vaccine was 33% against the delta variant.

Separately, the World Health Organization (WHO) said that delta, which first originated in India, would be the dominant strain in the world in the months to come.

It has been recorded in 124 territories — 13 more than last week — and already account for more than three-quarters of sequenced specimen in several countries.