The new coronavirus variant, Omicron, has been detected in two Israeli doctors, one of whom had returned from a conference in London in the past week, Israel's largest hospital confirmed Tuesday.
A spokesperson for Sheba Medical Center near Tel Aviv said the two doctors had received three doses of the Pfizer/BioNtech vaccine, and so far have shown mild COVID-19 symptoms.
The physician who had returned from Britain had probably infected his colleague, it said.
The doctors join the two previously confirmed Omicron cases identified in Israel earlier. One of them a tourist from Malawi who had received the AstraZeneca vaccine.
Israel shut its borders to foreigners from all countries for 14 days on Saturday to try to contain the spread of Omicron and has reintroduced counter-terrorism phone-tracking technology to trace contacts of a handful of people who have likely been infected.
Israel hopes that within those 14 days it will better know how effective COVID-19 vaccines are against Omicron.
Around 57% of the country's 9.4 million population is fully vaccinated.