The Pfizer-BioNTech COVID vaccine appears to largely prevent hospitalization and serious cases, but is significantly less effective against preventing the spread of the Delta variant of the coronavirus.
New Health Ministry figures reported by the Ynet news site indicated that over the past month, the vaccine, which has been the one used for almost all vaccinated Israelis, has been just 64 percent effective in preventing coronavirus infection. The data reportedly shows that during May, when the strain was less prevalent, the vaccine was 94.3% effective.
According to Ynet, the figures were presented Sunday evening at a meeting of a team of experts advising the government on its handling of the pandemic.
Meanwhile, a study from researchers at the Hebrew University and Hadassah University Medical Center indicated that the Pfizer vaccine is 60-80% effective against infection from the Delta strain.
The Delta variant, which is believed to be twice as contagious as the original strain of COVID-19, is thought to be responsible for 90% of new cases in Israel over the past two weeks.
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The Health Ministry figures, however, report that the vaccine is still considerably effective against preventing serious symptoms and hospitalization. During May that figure stood at 98.2%, according to the data obtained by Ynet, and during June it was 93%.
But the researchers at Hebrew University warned that it was too early to fully tell how effective the vaccine is at preventing hospitalization.
“Due to the recognized delay in serious morbidity (by about 10 days), there is not currently enough data to predict how the current wave of infections will be expressed in serious cases,” wrote the researchers.
They added that while serious cases are expected to rise in the coming weeks, data from Singapore and the UK indicate that the Pfizer vaccine is still overwhelmingly effective at preventing the most serious symptoms.
An Israeli youth receives a Pfizer-BioNTech COVID-19 vaccine in Rishon LeZion on June 6, 2021. (AP Photo/Sebastian Scheiner)
The researchers urged the government to take immediate measures to halt the current rise in cases,