Pfizer Vaccine Is About 30% Less Effective Against Delta Strain, Early Israeli Data Suggests

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Elizabeth Weibel Contributor
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The Pfizer-BioNTech vaccine is reportedly about 30% less effective in protecting against the new delta variant of the coronavirus, amidst a surge in infections in Israel.

While the Pfizer vaccine proved to have a 94% effectiveness rate against the coronavirus between May 2 and June 5, it’s efficiency rate dropped to about 64% between the months of June and July, Mediaite reported.

While initial research by the Maccabi Healthcare Services (MHS) in March showed that two weeks after individuals received the second dose of the Pfizer vaccine, there was a 99% efficacy rate in preventing COVID-19 and a 91.2% rate of preventing against infection, Israel’s Health Ministry announced on Monday that the efficiency rate had dropped to 64%, Haaretz reported.

In response to a rise in cases stemming from the delta variant, Israel reinstated their indoor mask mandate, just 10 days after lifting the mandate, BBC reported.

“We are seeing a doubling every few days,” the newly appointed Director-General for the Health Ministry, Nachman Ash explained in an announcement. “Another thing that’s worrying is that the infections are spreading.”

Nicknamed the “Delta” variant, it was first noticed in India and has since emerged in approximately 60 countries around the world, including the United States and the U.K. While the variant has not been found to be more deadly, it has been found to be more contagious than the other variants and can lead to severe illnesses. (RELATED: Study: COVID-19 Variant From UK Not Linked To More ‘Severe Disease Or Death’)

A study found that about half of adults in Israel who had been infected with the delta variant of the coronavirus had received their Pfizer vaccine.

While the efficiency rate from the Pfizer vaccine dropped, a study based on the blood samples of eight people who received their second dose of the Moderna vaccine showed that the vaccine proved to be effective against all variants of COVID-19, including the delta variant, according to a statement from the company on June 29.