A new study published this week by the Israel Ministry of Health found that while the Pfizer-BioNTech vaccine is highly effective in preventing severe cases of COVID-19 caused by the delta variant, it was much less effective than the agency Healthcare was previously thought to protect people from infection. .
The study, carried out June 20 to July 17 with results published in a report On Thursday, it found that inoculating two doses of Pfizer-BioNTech was approximately 88 percent effective in preventing hospitalization due to the delta variant, and approximately 91 percent effective in protecting against severe cases.
However, the Israeli health agency said that for symptomatic cases of COVID-19, the vaccine was found to offer about 41 percent protection against the delta variant, with an overall effectiveness of 39 percent in preventing infections of the delta. delta variant.
The new percentage is much lower than the 64 percent effectiveness against delta variant infections that Israel reported earlier this month.
The above figure generated widespread skepticism from health experts, who argued that mRNA vaccines like Pfizer’s injection have repeatedly been shown to offer strong protection against COVID-19 variants.
The initial Israeli report was also challenged by a Public Health England study published Wednesday in the New England Journal of Medicine that found the two-dose Pfizer vaccine to be 88 percent effective against the delta variant.
By comparison, the UK health agency said the AstraZeneca vaccine was 67 percent effective in preventing the delta strain infection.
Ran Balicer, chairman of Israel’s national expert advisory team on the response to COVID-19, said in a statement alongside Thursday’s report that his data could have been skewed, citing the ways in which groups of vaccinated people were assessed. versus those who had not. been vaccinated.
“The heavily skewed exposure patterns in the recent outbreak in Israel, which are limited to specific population sectors and localities,” means that some factors may not be taken into account, he said. according to Bloomberg.
“We are trying to complement this research approach with additional ones, taking into account additional personal characteristics,” added Balicer before noting that “this takes time and a greater number of cases.
Pfizer said in a statement Friday that it was confident in the protection offered by its two-dose vaccine, and BioNTech told Bloomberg it was reviewing data from the Israeli government.
The Israeli studies on the effectiveness of the delta variant vaccine were previously used by Pfizer earlier this month to suggest that people may eventually need a booster shot, although US health officials have said not. it is needed at this time.
An advisory panel from the Centers for Disease Control and Prevention (CDC) met Thursday morning to discuss whether it should recommend a COVID-19 booster shot for immunosuppressed people.