Professor Eran Segal, an expert at the Weizmann Institute of Science, on Tuesday said that at this stage, with the uncertainty regarding the Omicron variant of the COVID-19, there is no choice but to tighten restrictions and increase enforcement of the Green Pass.

He also said that restricting the unvaccinated from attending gatherings is a step which should be considered.

In an interview with Seder Yom, Prof. Segal, who is also an adviser to the Coronavirus Cabinet, said that in his opinion, the fifth wave has already begun in Israel.

"According to our analysis, there are two doublings a week in the number of Omicron cases, and there are conflicting reports regarding its virulence," he said.

"We saw that in the first stages, there is a value to limiting the number of people returning from abroad, but if the South African variant is already here and spreading, prevention at Ben Gurion Airport has marginal value when it comes to the outbreak."

Prof. Segal added that the best way to control the wave of infections is significant vaccination "as was proven in the past," and a fourth dose should be considered.