Israel announced Wednesday that it would start making fourth Covid-19 vaccine shots available to all vulnerable people aged over 18, continuing its drive to beat successive virus waves with top-up jabs.
Israel was among the first countries to launch mass Covid immunisation campaigns for its population.
On Wednesday, health ministry director Nachman Ash announced a new stage in the campaign, saying that all immunocompromised people and frontline workers over 18 would be eligible for a fourth shot.
He cited a study showing that a fourth dose of the Pfizer vaccine causes a three to fivefold increase in the number of antibodies in a vaccinated person, compared to someone who has received three doses.
More than 600,000 Israelis, out of a total population of 9.4 million, have received a fourth dose of vaccine, according to the health ministry's figures.
The country has seen daily new infection rates rocket to record highs in recent days as the Omicron variant sweeps the globe.
So far, Israel has recorded 8.513 deaths due to Covid-19.