Topline
Both the Pfizer-BioNTech and Oxford-AstraZeneca vaccines were at least 90% effective in preventing deaths in people who had tested positive for Covid-19 after receiving both doses of the shot, according to a new study from Scotland, confirming the effectiveness of the jab in the first country-wide study to measure its level of protection against the delta variant.
CARDIFF, WALES - DECEMBER 08: A member of staff poses with a phial of Pfizer-BioNTech Covid-19 ... [+]
Key Facts
The Pfizer shot proved 90% effective at preventing death in vaccinated individuals who tested positive while the AstraZeneca was found to be 91% effective, according to the University of Edinburgh study, which was published in the New England Journal of Medicine on Wednesday.
No deaths occurred among those ages 16-39 who were fully vaccinated.
Pfizer was found to be 88% effective for vaccinated individuals ages 40-59; AstraZeneca was 95% effective.
For the 60-or-older age group, Pfizer was 90% effective, with AstraZeneca at 87%.
Sequencing data from the study showed that 99.5% of the infections were caused by the delta variant.
No deaths were recorded in those who have been vaccinated with the Moderna shot, and as a result researchers were unable to measure effectiveness (figures were not included in the study).
Big Number
114,000. The number of people from which a mortality analysis was taken for the study. Overall, it drew data from Scotland’s entire 5.4 million person population (1.5 million adults were tested) between April 1 and Sept. 27. The study is notable as it is the first to draw from a country-wide sample size since the delta variant became the dominant strain.
Key Background
The CDC says the delta variant is more than twice as infectious as the alpha variant, and cites data that suggests that those who are unvaccinated could experience more severe illness from the delta as opposed to the alpha.
What We Don’t Know
This study pertains to deaths as a result of the delta variant among vaccinated people, not whether the vaccine is more or less effective at preventing people from contracting the delta variant.
Tangent
A new descendant of the delta variant, which has been labeled AY.4.2, is currently spreading across the U.K., accounting for 6% of positive tests as of Sept. 27, a U.K. Security Agency report suggests.
Further Reading
Pfizer’s Covid Vaccine 93% Effective At Preventing Teen Hospitalizations, CDC Study Finds
Prior Covid Infection Is As Effective At Preventing The Virus As Vaccination, U.K. Study Suggests
