Israel says the Delta variant is infecting vaccinated people – as many as 50% of cases. But they are less severe.

• As many as half of new COVID-19 cases in Israel are in vaccinated people, health officials said.
• Israel's new cases are driven by the Delta variant, which is not as easily beaten by vaccines.
• The figure is likely an estimate, as the ministry is still analyzing data from the cases.
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As Israel is facing a surge in cases driven by the Delta variant, its health officials said as many as half of those are among people who were vaccinated.

Fully vaccinated people who were in contact with the Delta variant will now have to quarantine, according to Chezy Levy, the leader of Israel's Health Ministry's director-general.

"Even though the numbers are low, the fact that this is reaching vaccinated people means…that we are still checking how many vaccinated people have also been infected," Levy said, Haaretz reported Wednesday.

Talking with state broadcaster Kan Bet public radio, Levy said that approximately 40 to 50% of new cases were people who had been vaccinated.

The figure is likely to be an estimate, as the ministry is still analyzing data about the cases. On Monday, Levy's estimate was lower: he said only a third of the new daily cases were people who had been vaccinated.

It is also not clear whether those would have been fully vaccinated or received only one shot of the vaccine.

Although they are preliminary, the figures underline the worry that the Delta variant could see the virus continue to spread even in widely-vaccinated places like Israel.

Cases in Israel have been over 100 per day for over a week now - the highest level there since May. About 70% of those were caused by the Delta variant, Levy said on Monday.

Israel had been marking an end to its virus restrictions. It ended indoor masking last week, with daily COVID-19 cases hovering in the single digits.

As of June 24, about 57% of Israel's population was fully vaccinated, according to John Hopkins University data.

Although the infections among vaccinated people have alarmed Israelis, the infections do not appear to be as severe as in unvaccinated people, only rarely leading to hospitalization or death.

As of Monday no severe cases of COVID-19 had been reported from the latest surge, Ran Balicer, public health director for Clalit said in a tweet.

The Delta variant could pose the greatest risk to vaccinated persons of all the variants. It is known to be better able to break through one dose of two dose-regimen vaccines, such as the Pfizer and AstraZeneca vaccines.

On Monday, Dr Mike Ryan, the executive director of WHO's health-emergencies program, said Delta could "be more lethal because it's more efficient in the way it transmits between humans."

Two doses of the vaccines appear to be protective against Delta. But no vaccine is 100% effective, and so-called breakthrough cases are still possible.

With previous variants, those breakthrough infections were mostly mild.

In the UK, where the Delta variant makes up more than 90% of cases, 26 of 73 deaths associated with Delta were among people who had been fully vaccinated, according to The Telegraph.