Israel’s Health Ministry: Pfizer Vaccine Less Effective in Preventing Delta Variant

JERUSALEM, Israel - Israel's Health Ministry released data on Monday indicating that the Pfizer coronavirus vaccine is largely effective in preventing serious cases and hospitalizations, but is significantly less effective in preventing the spread of the Delta variant. 

The ministry said the vaccine's ability to stop symptomatic coronavirus infections has dropped to 64% as the Delta variant continues to spread in Israel. Before the surge of the Delta variant, Israeli data showed the Pfizer vaccine to be 94.3% effective in preventing new infections. 

Despite the reported drop, Health Ministry data show the vaccine to be 93% effective at preventing hospitalizations and serious cases. 

However, some Israeli health experts, including members of the ministry’s epidemiology team have questions about its analysis of infection rates in the country, Haaretz reports.

"There are enormous methodological challenges in properly assessing the efficacy of the vaccine from local outbreaks," one health expert told Haaretz. 

On Monday evening, the Health Ministry said there are some 2,700 active cases in the country and an overwhelming majority are believed to be caused by the Delta variant. 

Currently, about 70 people are hospitalized with COVID infections in Israel and 35 are in serious condition. Last week there were 22 people in serious condition. 

The increase in infections caused the government to reintroduce the indoor mask mandate, which had been previously lifted. 

Israeli Prime Minister Naftali Bennett and Health Minister Nitzan Horowitz directed the Health Ministry to promote research on the potential need for a third vaccine dose.

Bennett said the research would “evaluate the efficacy of the vaccine and the rate at which it wears off over time.”

However, the Health Ministry clarified that “there is no recommendation or decision at this stage to vaccinate the general public in Israel with a third dose.”