By Jason Douglas


New data from a large study of elderly people in the U.K. provides further evidence that vaccines against Covid-19 are highly effective after just one dose.

British researchers said in preliminary findings published online Monday that a single dose of the Covid-19 vaccines developed either by Pfizer Inc. and BioNTech SE or the University of Oxford and AstraZeneca PLC reduced the risk of hospitalization among the over 70s by 80%, compared with those of a similar age who weren't vaccinated.

The study, which hasn't yet been reviewed by other scientists, looked at health records associated with 7.5 million people over 70 in England, making it one of the largest such studies published to date.

The data provide further strong evidence the vaccines being rolled out across the world are potent weapons against Covid-19. They should also help dispel concerns in parts of Europe that AstraZeneca's shot doesn't have enough data to back up its rollout to at-risk over-65s.

The scientists found a single dose of either vaccine reduced the risk of symptomatic Covid-19 and hospitalization from as little as 10 days after injection, with the strongest effects seen after 28 days.


Write to Jason Douglas at


(END) Dow Jones Newswires

March 01, 2021 13:12 ET (18:12 GMT)

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