Israel has approved a fourth vaccine dose for people most vulnerable to Covid-19, becoming the first country to do so as it braces for a wave of infections fuelled by the Omicron variant.
Nachman Ash, the director general of Israel's Health Ministry, announced the decision at a press conference late on Thursday (local time).
He says the decision is based on early research, and that officials will consider expanding the administration of a fourth dose to more of the public as they assess the situation.
Israel was among the first countries to roll out Pfizer's coronavirus vaccine a year ago and began freely offering boosters last summer. But it still saw a wave of infections blamed on the Delta variant, and officials have warned of another driven by the fast-spreading Omicron.