In a new report, Israel’s health ministry said Pfizer’s COVID-19 vaccine is just 39% effective in its country now that the Delta variant has emerged as the dominant variant. However, Israel said local data showed that the two-shot vaccine is still highly effective at preventing severe illness (88%) and in reducing the need for hospitalization (91%).
The Israeli statistics, which were published Thursday, do not align with recent data from the U.K. showing that Pfizer’s vaccine was 88% effective against symptomatic disease caused by the Delta variant.
Critics say Israel’s data could be skewed due to the fact that a significant percentage of the COVID-19 tests in the country were conducted among the elderly and in areas with high case numbers. Only a small number of young and vaccinated people were tested.
Israel, which started vaccinating its population before many other countries, has already begun administering a third dose of Pfizer’s vaccine to adults with compromised immune systems. At this time, U.S. officials don’t think it’s necessary to administer booster shots to Israel’s general population.
Pfizer eyes booster dose authorization
Earlier this month, Pfizer said it intends to seek booster dose authorization from the FDA in light of the data coming out of Israel.
"It's a small data set, but I think the trend is accurate: Six months out, given that Delta is the most contagious variant we have seen, it can cause infections and mild disease," said Mikael Dolsten, Pfizer's chief scientific officer.
Following Pfizer’s announcement, U.S. health officials quickly issued a statement assuring vaccinated Americans that they remain protected against the virus. The agencies added that companies don’t have the authority to decide when booster shots are needed.
"Americans who have been fully vaccinated do not need a booster shot at this time," the FDA and CDC said in a joint statement. "We continue to review any new data as it becomes available and will keep the public informed. We are prepared for booster doses if and when the science demonstrates that they are needed.”
Americans who are fully vaccinated are “protected from severe disease and death, including from the variants currently circulating in the country such as Delta," the agencies added.