Pfizer booster shots ‘do give increased protection against Delta’
A 70% to 84% reduced risk of testing positive was seen two to three weeks after a third jab, according to a study
A third shot of the Pfizer-BioNTech Covid-19 vaccine provides added protection against the coronavirus during a Delta outbreak, according to early data from Israel, where boosters began rolling out incrementally in mid-July.
People who received the supplemental dose had a 48% to 68% lower risk of infection a week to 13 days later, compared with those who got the standard two-dose regimen, a preliminary analysis of data from Maccabi Healthcare Services found. The protection increased with time, with a 70% to 84% reduced risk of testing positive two weeks to 20 days after getting a third shot.
The research, released on Tuesday ahead of peer-review and publication, assessed the additional effectiveness of a booster shot against infection due to the Delta variant, but not severe disease, according to researchers led by Daniel M Weinberger, an associate professor of epidemiology at the Yale School of Public Health in New Haven, Connecticut...