Mounting COVID-19 tally in Israel, where most citizens are immunized with the Pfizer/BioNTech vaccine, offer “a preliminary signal” that the vaccine may be less effective in preventing mild illnesses from the Delta variant, a top expert said on Monday.
Nonetheless, Ran Balicer, chairman of Israel’s national expert panel on COVID-19, stressed it was “too early to precisely assess vaccine effectiveness against the Delta variant” first recognized in India in April which is surging across the globe.
The situation is partially due to the overall low number of cases among completely vaccinated Israelis which are not consistently distributed across the population, further confusing efforts to reach conclusions about the data.
Balicer, also the chief innovation officer at Clalit, Israel’s largest health maintenance organization (HMO), told AFP that the Delta variant’s emergence as the “dominant strain” in the country has led to a “massive shift in the transmission dynamic.”
About half of the daily cases are among children, and half are among mostly vaccinated adults.
The number of severe cases among vaccinated Israelis has risen in recent days from roughly one every two days up to five cases per day, Balicer said.
He further said it was also too early to draw conclusions about the vaccine’s effectiveness against serious illness caused by the Delta variant.
But, he added, experts “remain hopeful that the vaccine effectiveness against serious illness will remain as high as it was for the alpha strain” identified for the first time in Britain in December.
Israel’s vaccine rollout that began in December was one of the world’s fastest, making the Jewish state a closely-watched case study on whether mass inoculation offers a path out of the pandemic.
Vaccinations had brought transmission down to about five new cases per day, but that figure has risen to around 300 in recent days, with the Delta variant raging.