A single dose of the AstraZeneca vaccine reduces the risk of death with COVID-19 by approximately 80 per cent – and two doses of Pfizer cut it by 97 per cent, the latest data suggests.


Health Secretary Matt Hancock described the news as “life-changing” for people across the country as he urged everyone to take up their offer of a jab.

The latest data shows for the first time protection against mortality from the Oxford/AstraZeneca vaccine and the additional protection provided by two doses of the Pfizer vaccine.

For its analysis, Public Health England (PHE) said it looked at the number of new symptomatic PCR positive cases between December and April, and those who died within 28 days of their positive test and compared them according to vaccination status.

Results shows that COVID-19 cases who had had a single dose of either the Pfizer or the AstraZeneca vaccines had similar levels of protection against mortality – at 44 per cent and 55 per cent respectively – compared with people who had not had a coronavirus vaccine.

When they took into account the protection the jab provided against catching the coronavirus, PHE said this is equivalent to approximately 80 per cent protection against death in people who have had a single jab.

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PHE said the data shows that protection against mortality from the Pfizer vaccine is even higher – around 69 per cent – for people who had their second jab at least seven days before testing positive for the virus.

Combining this with the estimated protection from getting the virus, it is equivalent to an estimated 97 per cent protection against death in people who have had both doses of Pfizer, PHE added.

The health body said a separate report it had done showed that for people aged over 80, the risk of admission to hospital with the virus is reduced by an estimated 93 per cent after two doses of Pfizer.

Dr Mary Ramsay, head of immunisation at PHE, urged people to follow through and get both doses of a vaccine when offered.

“This analysis gives us even more reassurance that the vaccine is highly effective in protecting adults against death and hospitalisation from COVID-19," she said. “Getting your vaccine will significantly reduce your risk of dying or becoming seriously ill from COVID-19.

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“It will also significantly reduce your chances of getting infected and infecting others. It is vital to get both doses of your vaccine when you are offered it.”

Jonathan Ball, professor of molecular virology at the University of Nottingham, said the results are “an incredible outcome” which “paves a way out of this, and future, lockdowns”.


“To realise the full benefits, we need to get as many people vaccinated as possible," he said. “Then, when this has been achieved we should move towards good surveillance and monitoring vaccine effectiveness instead of relying on isolation and other restrictive measures, as we learn to live with the virus.”

Reader Q&A: Could dinosaurs have caught COVID-19?

Asked by: Christian Jones, Llanelli

We can’t know for sure if a dinosaur could be infected with COVID-19, but studies of coronavirus genomes indicate that they originated after the dinosaurs went extinct. There is evidence that dinosaurs were affected by other diseases, however.

Palaeontologists have identified many ‘palaeopathologies’ on dinosaur bones, which indicate various maladies including bone cancer, gout, a bone infection called osteomyelitis and infestation from parasites.

In one famous case, the Tyrannosaurus rex skeleton nicknamed ‘Sue’ was found to have many holes in its lower jawbone. The holes are similar to injuries seen in modern-day birds infected with a parasite called Trichomonas, which makes it difficult to swallow and breathe.

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Sara RigbyOnline staff writer, BBC Science Focus

Sara is the online staff writer at BBC Science Focus. She has an MPhys in mathematical physics and loves all things space, dinosaurs and dogs.