A large, realistic study of half a million people has shown that the BioNTech-Pfizer coronavirus vaccine is 94% effective.
The article was published in the New England Journal of Medicine Wednesday and involved in studying 1.2 million people during Israel’s massive vaccination campaign.
What has the investigation revealed?
The study showed that two injections of the BioNTech-Pfizer vaccine reduced symptomatic COVID-19 cases by 94% in all age groups, while a single injection was 57% effective in protecting against symptomatic infections after two weeks.
The vaccine was also found to be 92% effective at preventing serious illness after two injections and 62% after one, the peer-reviewed study found.
The results of the study were close to those of last year’s clinical trials for the Pfizer-BioNTech vaccine, where two doses were found to be 95% effective.
It showed that there could be a strong protective advantage against infection, a factor considered critical in breaking through further transmission.
How was the research conducted?
The study was led by researchers from the Clalit Research Institute and Ben-Gurion University of the Negev in Israel, along with Harvard University in the United States.
The study was conducted between December 20, 2020 and February 1, 2021, when the British variant of the coronavirus spread in Israel.
The study compared nearly 600,000 people aged 16 and older in Israel’s largest healthcare organization who received the Pfizer-BioNTech doses in December or January with an equal number of people of similar age, gender, and health who did not receive the injection.
None of the participants had contracted the virus in the past.
Lead author Noam Barda, chief of epidemiology and research at the Clalit Research Institute, told AFP news agency that the matching process was very robust.
The results were then recorded on days 14-20 after the first admission and day seven or later after the second.
Researchers ‘surprised’ by results
Senior study author Ran Balicer said the results showed that the BioNTech-Pfizer vaccine is “extremely effective in the real world” after the second dose.
“We were surprised because we expected that in the real world, where the cold chain is not perfectly maintained and the population is older and sicker, you will not get as good results as in the controlled clinical trials,” said Balicer. Reuters news agency.
“We have shown that the vaccine is equally effective in very different subgroups, in the young and the elderly, in those without co-morbidity, and in those with little co-morbidity,” he added.
dvv / rs (AFP, AP, Reuters)