Pfizer-BioNTech firing could help end pandemic, Israeli study finds

Pfizer Inc. and BioNTech SE’s COVID-19 vaccine was extremely effective against the virus in a study that followed nearly 1.2 million people in Israel, the results which public health experts say show that vaccinations could end the pandemic.

Two doses of the vaccine prevented 94% of COVID-19 cases in 596,618 people vaccinated between December 20 and February 1, of whom about a quarter were over 60 years old, teams from the Clalit Research Institute and the University reported. from Harvard in a study published Wednesday in the New England Journal of Medicine.

The researchers matched each person vaccinated with one who had not been vaccinated, resulting in the best analysis to date on whether the extremely good results from an earlier clinical trial could hold up in the real world. Pfizer-BioNTech’s shot cleared all obstacles. It was so effective, in fact, that outside experts said that with enough wide use, it might be possible to bring the pandemic to an end.

“This is the kind of vaccine that gives us hope that herd immunity is possible,” said Raina MacIntyre, professor of biosafety at the University of New South Wales in Sydney who did not attend the study. At the levels of effectiveness seen in Israel, she said, vaccinating about 60% to 70% of the population should be enough to prevent infections as well as illness and death and “have the best chance of resuming. a normal life and to open up society ”.

After two doses, the vaccine was just as effective for adults 70 years of age and older as it was for younger people. There were indications that the vaccine might work somewhat less well for people with three or more other conditions, such as high blood pressure and diabetes. But the benefit remained significant, with 89% protection against COVID-19 symptoms seven days after the second dose.

And for most people, protection was already important two to three weeks after the first dose.

The results were also positive for another closely watched characteristic: prevention of transmission. Although the research team noted that the study was not designed to study transmission, because the participants were not proactively tested, there appears to be an effect: 92% of all Documented infections, including those that were asymptomatic, were avoided in those vaccinated. .

“We are able to get a concrete measure of vaccine effectiveness,” said Ben Reis, study co-author and director of the Predictive Medicine group at Boston Children’s Hospital and Harvard.

This was the largest study to date to quantify the impact of the vaccine outside the strict limits of a randomized, blinded clinical trial to measure efficacy for regulators. This gave researchers a chance to see if any deviations from immunization schedules or logistical issues for the vaccine, which must be kept frozen, would alter the results.

It is important to note that at the end of the study period, up to four-fifths of infections in Israel belonged to the most infectious variant of the virus first identified in the UK, resulting in more information that was missing from the results of the clinical trial of the vaccine, which was conducted before the variant began to spread widely.

The new study results suggest that “the vaccine offers at least some protection against this variant as well,” said Zoe McLaren, associate professor in the School of Public Policy at the University of Maryland, Baltimore County. McLaren, who was not involved in the study, said some sources of bias, such as differences in testing rates or risk of exposure, might remain between those who had been vaccinated and those who did not. had not done. But the conclusion remains unchanged, McLaren said.

“This is all very good news,” she said. “The implications of this study are clear: high levels of vaccination in the population will reduce transmission and keep cases low.”

The study is the latest in a string of positive results in Israel, which has the highest COVID-19 vaccination rates in the world. In an effort to get as good a comparison as possible, organizers sought to match each person vaccinated with as similar as possible who was not vaccinated.

For example, an ultra-Orthodox Jewish man from a certain neighborhood, with a number of flu shots over the past five years and two other medical conditions would be paired with an ultra-Orthodox man of about the same age, from the same neighborhood, and with the same number of previous vaccinations and medical conditions, said Noa Dagan, director of data and AI-based medicine at Clalit.

“It’s very, very specific to make sure it’s really what we call tradeable,” Dagan said. “As you can imagine, this process is not that simple.”

Finding those comparisons will become even more difficult as Israel’s vaccination campaign continues, narrowing the pool of potential unvaccinated comparators, she said. But the researchers plan to continue as long as possible, with more data updates planned.