JERUSALEM (Reuters) – Israel is giving weekly data updates on its COVID-19 outbreak to vaccine maker Pfizer under a collaboration agreement that may help other countries fine-tune their inoculation campaigns and achieve “herd immunity,” officials said.

Israelis began receiving first shots of the vaccine developed by Pfizer and its German partner BioNTech on Dec. 19 in one of the world’s fastest vaccination rollouts.

Israel’s Health Ministry made public most of a 20-page collaboration agreement it signed with Pfizer, which said the aim was “to determine whether herd immunity is achieved after reaching a certain percentage of vaccination coverage in Israel”.

Commercial details such as price and quantity of vaccine shots supplied were not made public, but the agreement said that Israel was relying on Pfizer to deliver enough doses at a fast enough rate to allow it to achieve “herd immunity,” meaning a sufficient portion of the population is immune to the virus.

“While this project is conducted in Israel, the insights gained will be applicable around the world and we anticipate will allow governments to maximize the public health impact of their vaccination campaigns,” BioNTech said on Monday in a statement.

This includes determining potential immunization rates needed to stop the virus from spreading, it said.

The goal, BioNTech said, was “to monitor the evolution of the epidemic over time and at different vaccination rates.”

“This will help us understand whether a potential decrease in cases and deaths can be attributed solely to direct vaccine protection or to both direct and indirect (or ‘herd’) protection,” it said.

During weekly status reports, Israel will provide Pfizer with epidemiological data such as: the number of confirmed COVID-19 cases, hospitalizations, how many patients were on ventilators, how many died, as well as an age and other demographic breakdown.

Such data was available to the public and keeps patients anonymous, Israeli officials said.

About a quarter of Israelis have received their first vaccine shot and 3.5% already got their second dose.

Still, the country is in its third lockdown with infection rates remaining high. More than half a million cases have been reported and 4,005 people have died in Israel since the pandemic began.

(Reporting by Ari Rabinovitch, Ludwig Burger, Nikolaj Skydsgaard and Steven Scheer; Editing by Alex Richardson)