By Dov Lieber

TEL AVIV -- The latest data from Israel shows a 94% drop in symptomatic Covid-19 infections among 600,000 people who received two doses of Pfizer Inc. and BioNTech SE's vaccine, offering important new insights to other countries as they roll out their own campaigns.

The vaccinated group was also 92% less likely to develop severe illness from the disease, according to a study by Clalit, Israel's largest healthcare provider. Clalit compared 600,000 people who got the shots with a group of the same size who didn't -- in what was the country's largest vaccine study to date.

Clalit said the study, which was carried out with a team from Harvard University, included 430,000 people who were between 16 and 59 years of age, and 170,000 who were 60 or older. It was the first of its kind to show such a high level of efficacy for Pfizer's vaccine for those aged 70 and over, due to the limited scope of the clinical trials, according to the healthcare provider.

The study was done so that each vaccinated individual was tested against an unvaccinated person who had a similar profile, including their risk level for infection, risk level of developing serious illness and overall health.

"It is now unequivocal that Pfizer's vaccine against the coronavirus is incredibly effective in real life one week after the second dose, just as was found in the clinical study," said Ran Balicer, Clalit's chief innovation officer and one of the study's authors, in a Hebrew statement published Sunday with the study. The vaccine is even more effective two weeks after the second shot, he added.

The small Middle Eastern country, which leads the world in vaccinating against Covid-19 in terms of percentage of the total population inoculated, has already administered the first shot of a recommended two-dose regimen to about 42% of its roughly nine million population since beginning its program on Dec. 20. About 28% of the entire population is fully vaccinated, according to data from Israel's health ministry.

After beginning its vaccine campaign with healthcare workers and those over 60 years old, Israel earlier this month opened it up to everyone over 16.

Israel aims to inoculate most of its population by March, a goal made possible after it paid a premium for early shipments from Pfizer and agreed to share data about its vaccine -- from effectiveness to side effects. It also placed orders with other vaccine companies, including Moderna Inc. and AstraZeneca PLC.

After imposing a third lockdown in December to contain a resurgence in infections, Israel in recent days has loosened restrictions somewhat. It has allowed unrestrained travel within the country, opened national parks, allowed takeaway service from restaurants and permitted larger outdoor gatherings. But most schools and businesses remain closed and nearly all international flights are banned.

Israel temporarily shut its only international airport late last month to halt the spread of new coronavirus variants in the country. Authorities say the more infectious and possibly more deadly British variant, known as B.1.1.7, has become the dominant strain in Israel over the past month.

In recent days, the country's overall daily infections have greatly decreased, dropping from a seven-day average of over 8,000 daily infections in mid-January to below 5,000 on Monday.

Israel's government is currently working on ways to reward those who have taken the vaccine. The government is looking to reopen restaurants, museums and cultural sites to vaccinated people in the coming weeks. It is also working on tourism deals with nearby Cyprus and Greece to allow inoculated Israelis to soon travel there without quarantining.

While Israel only began gradually exiting a strict lockdown eight days ago, researchers at the central-Israel-based Weizmann Institute of Science found that in relation to previous lockdowns, hospitalizations and serious illness among those first vaccinated, meaning those 60 and older, dropped 48%, while deaths decreased 50% among that group. For those aged 55-60, the next most-vaccinated group, researchers found a 36% decrease in hospitalizations and 30% decrease in serious illness.

"Gradually the groups that are further away from their vaccination start date become less and less hospitalized," said Eran Segal, a computational biologist at the Weizmann Institute. "It's beautiful."

(END) Dow Jones Newswires

02-15-21 1020ET