11:43 a.m. ET, October 14, 2021
Booster shots are as safe as the initial vaccine doses, Israeli health officials tell FDA advisers
From CNN's Jacqueline Howard
Paul Ellis/AFP/Getty Images
Covid-19 booster doses appear to have similar side effects as the initial first and second doses — and no increased risk of allergic reaction or the heart condition myocarditis, Israeli health officials said on Thursday.
In a meeting of the US Food and Drug Administration's Vaccines and Related Biological Products Advisory Committee, Dr. Sharon Alroy-Preis of Israel's Ministry of Health and Ron Milo of the Weizmann Institute in Israel presented data on the use of Covid-19 booster doses in their country, detailing safety data from the nationwide booster campaign.
Compared with first and second doses, third doses of coronavirus vaccine "have the same amount of adverse events, not more," Alroy said. "We're not seeing huge amounts of allergic adverse events post the third dose." Most people in Israel received the Pfizer vaccine.
Among 3.7 million booster doses administered, there were 2,394 reports of non-serious side effects, the data showed.
When it comes to serious adverse events, "for 3.7 million booster doses administered, we had 44 serious adverse events reported, and for those adverse events, we have a special committee that looks into each and every case," Alroy-Preis said.
The mRNA Covid-19 vaccines made by Pfizer and Moderna have been linked to rare cases of heart inflammation, myocarditis and pericarditis, and warnings were added to the vaccines’ fact sheets in the United States; studies have shown the cases are typically mild.
Among 2.5 million vaccinated people, "we had nine cases of myocarditis and eight cases of perimyocarditis. So altogether, 17 cases of either myocarditis or perimyocarditis," Alroy-Preis said. "We're not seeing an increased risk of those events following the booster dose."
Overall, "the booster dose adverse events are not more acute than the first or second dose, and their rates of occurrence is not higher," Alroy-Preis said.
"The administration of the booster dose helped Israel dampen the infections and severe cases in the fourth wave. We are now coming out of a fourth wave that, without the booster dose I believe, would have put us in a worse place with a high burden on hospitals," Alroy-Preis said. "We were able to get out of this wave due to the booster dose."