As the Delta strain spreads throughout Israel, the effectiveness of the coronavirus vaccines in preventing infection has dropped considerably and now stands at 64% down from 94%, according to data presented to Health Ministry officials late Sunday.
The reduction in the vaccine's efficacy was registered from June 6, five days after Israel lifted almost all coronavirus restrictions. Haaretz newspaper on Monday quoted ministry officials as saying that genetic sequencing showed the Delta strain was responsible for 90% of new COVID-19 cases over the past two weeks.
According to the Health Ministry, data collected between May 2 and June 5 - before the recent outbreak - showed the vaccines had 94.3% efficacy at preventing infection.
A similar drop was observed in effectiveness at preventing serious illness among those who received two doses of the vaccine, with 55% of the new infections found among the fully vaccinated population.
In the period between May 2 and June 5, there was a 98.2% protection from serious illness but after June 6 and until July 3, protection dropped to just 93%.
However, the vaccines were found to be still effective against serious illness that could lead to hospitalization.
A senior health official said on Sunday that the recent data was a real cause for concern.
"Vaccines appear to be less effective," the official said. "It is imperative that Israelis returning from travel abroad be tested five days after their arrival, in addition to tests conducted at the airport. The ministry should also consider a booster shot for the immunosuppressed and elderly population," he said.
In a meeting at the ministry on Sunday, no decision was made to provide a third vaccine for the population at risk, but officials said they were monitoring the situation. Some doctors treating coronavirus patients in the country's hospitals urged the ministry to provide the booster shots.
A member of the ministry's pandemic response team said he believed most physicians agree, but noted that not all immunosuppressed patients react the same to vaccines.
Prime Minister Naftali Bennett and Health Minister Nitzan Horowitz were to meet Monday to discuss the renewed spread of disease and the coronavirus cabinet was set to meet on Tuesday to consider the reinstitution of restrictions to stop the spread of the virus.
Among options being considered were imposing limits on the number of people allowed to congregate and a return to the "Green Pass" regulations that restrict the non-vaccinated population.
Other options include limiting the number of children allowed to congregate indoors.
The Health Ministry said that 292 people were diagnosed on Sunday after 37,000 tests were conducted, indicating a 0.7% positivity rate.
Hospitals were treating 63 patients suffering from virus complications, 34 of them said to be in serious condition with 16 on ventilators.
First published: 08:20, 07.05.21