A real-world trial of the Pfizer COVID-19 vaccine in over half a million people proves that it is highly effective in preventing serious illness or death, even after a single dose.
Wednesday’s published results, from a major vaccine campaign in Israel, provide strong confidence that the benefits seen in smaller, limited trials continued as the vaccine was used much more widely in a general population with different ages and health conditions.
The vaccine was 92% effective in preventing serious infections after two pictures and 62% after one. Its effect for preventing death was 72% two or three weeks after the first sighting, a rate that may improve as immunity builds over time.
It looked so effective in people over 70 and in younger people.
This is very encouraging … better than I would have thought, said Dr. Gregory Poland at the Mayo Clinic.
Dr Buddy Creech from Vanderbilt University agreed: Even after a single dose we see very high efficacy in preventing death, he said.
One doctor was not involved in the Israeli study but both are involved in another coronavirus vaccination operation.
Both doctors also said the new findings could increase consideration of delayed second sight, as the UK tries, or gives one dose instead of two to people on COVID- 19 already, as France is doing, to extend limited supply.
I would rather 100 million people have one dose than see 50 million people have two doses, Creech said. I see a lot of confidence on a single dose in Israel’s results, published by the New England Journal of Medicine.
The vaccine, made by Pfizer and its German partner BioNTech, is given as two shots, three weeks apart, in most countries.
The study was led by researchers from the Clalit Research Institute and Ben-Gurion University in the Negev in Israel, with Harvard University in the USA. It did not describe the safety of the vaccine, just efficacy, but did not reveal unexpected problems in previous trials.
Researchers compared nearly 600,000 people 16 and older in the largest health care group in Israel who received sightings in December or January to an equal number of people of the same age, gender and health who did not received the vaccine. None of the participants had tested positive for the virus.
The vaccine was considered 57% effective in preventing any symptoms of COVID-19 two or three weeks after the first dose, and 94% a week or more after the second dose. .
Efficacy was 74% after one picture and 87% after two for hospital prevention, and 46% and 92% for prevention of confirmed infection. Reducing infections hopes that the vaccine could stop the spread of the virus, but this type of study cannot confirm whether this is true.
There were 41 COVID-19-related deaths, 32 of which were in vaccinated individuals.
Overall, the numbers compare well to the 95% effectiveness after two doses seen in the restricted trial that forced U.S. regulators to allow emergency use of the vaccine, the spokesman said. Poland. The benefit of a single dose is a big question, and now there is some data to help inform the debate, he said.
Perhaps the right thing to do here is to protect as many people as possible… give everyone a single dose as soon as you can. I think that’s a very appropriate strategy to consider, Poland said.
Israel has now vaccinated nearly half of its population. A more recent variant of the virus that was first identified in the United Kingdom became mainstream in Israel during the study, so the results also provide some insight into how well the vaccine is being tested. performance against it.
Earlier this week, two UK studies suggested benefits even after one dose of the Pfizer vaccine or another from AstraZeneca. The UK is delaying the second sight for up to 12 weeks after the first tried to provide a level of protection for more people.