Pfizer COVID-19 Vaccine Less Effective Against Delta Variant, Says Israeli Study

July 27, 2021

A new Israeli study has found that the Pfizer vaccine provided much lower efficacy against COVID-19 infections during a four-week period when the Delta variant became prevalent in that country.

According to the study conducted by the Israeli Ministry of Health, the vaccine was only 39 percent effective at preventing COVID-19 infection and just 40.5 percent effective at preventing symptomatic disease. However, it was 88 percent effective at preventing hospitalization and 91.4 percent effective at preventing severe COVID-19 infections.

The findings were based on the monitoring of hundreds of fully vaccinated individuals between June 20 and July 17.

Israel has relied heavily on the Pfizer vaccine and boasts higher vaccination rates than the U.S. The country has also been in the forefront of a push for a third or booster dose of the Pfizer vaccine, which the Centers for Disease Control and Prevention and the FDA say is not necessary at this time.

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