If you’ve been waiting for more information to get your COVID-19 booster shot, the latest research from Israel suggests just how big of a difference a third dose can make—especially for young people. In the recent study, people 16 to 49 years old were 13 times less likely to test positive for COVID-19 after a booster shot of the Pfizer-BioNTech, even as coronavirus cases in the country surged. The strongest protection began two weeks after the third dose and continued until the study ended a few weeks later.
What’s interesting about this study is that it was comparing boosted people to fully vaccinated people—and the improvements in immunity were still significant. The researchers used data from the Israel Ministry of Health starting on July 30 to October 10, 2021, ultimately including more than 4.5 million people over the age of 16 who received the Pfizer vaccine at least 5 months prior. Then they compared rates of confirmed infection, severe illness, and death between vaccinated people who received a booster dose and vaccinated people who did not.
The results, published in The New England Journal of Medicine, were promising for other age groups too. Israelis age 50 and up who got their booster were around 10 times less likely to test positive for COVID-19 during the length of the study. And they drove down cases of severe illness and death—people 60 and over, in particular, were 12 times less likely to get severely ill compared to vaccinated people who didn’t receive the third shot and about 15 times less likely to die.
Of course, the omicron variant wasn’t a factor at the time the research was conducted. But there’s reason to be hopeful anyway. Pfizer and BioNTech announced Wednesday that laboratory tests suggest a booster shot offers protection against the omicron variant. That was based on a study that took blood samples from people who had received two doses of the Pfizer vaccine and also looked at samples from people who received a booster dose one month prior.
Fully vaccinated people saw a 25-fold reduction of neutralizing antibodies against omicron compared to the original coronavirus strain—although the company emphasized that the number of vaccine-induced T-cells leads them to believe full vaccination will still prevent severe illness and death.
But people who received a booster dose had 25 times the number of antibodies, and also increased the number of specific T-cells that should work against the omicron variant too. “Although two doses of the vaccine may still offer protection against severe disease caused by the omicron strain, it’s clear from these preliminary data that protection is improved with a third dose of our vaccine,” said Albert Bourla, chairman and chief executive officer for Pfizer in a press release.
However, it’s worth noting that the study was small—they looked at just 39 samples—and the results are preliminary. We’ll learn more about the real-world effectiveness of vaccines and boosters against the omicron variant as time goes on.
The U.S.’s other two vaccine manufacturers, Moderna and Johnson & Johnson, have not yet released information about the effectiveness of their vaccines against omicron. …….