An Israeli study appears to support findings from Pfizer and BioNTech that three doses of their vaccine, including a booster as well as an initial two-shot regimen, provide strong protection against the omicron variant, Reuters reported.

The blood samples of 20 people who received a third shot of the Pfizer-BioNTech vaccine one month ago and those of 20 people who received a second dose of the vaccine between five and six months ago were analyzed by researchers from the Israeli Ministry of Health’s Central Virology Laboratory and Sheba Medical Center, according to the news outlet. 

The director of the Infectious Diseases Unit at Sheba Medical Center, Gili Regev-Yochay, said that while there was no neutralization ability against the omicron variant in those who had received their second shot five or six months ago, “the good news is that with the booster dose it increases about a hundred fold,” Reuters reported.

“There is a significant protection of the booster dose,” she added.

However, she also said that the protection offered against omicron “is lower than the neutralization ability against the Delta, about four times lower.”

Earlier this week, Pfizer and BioNTech said that the omicron variant was neutralized by a three-dose series of their vaccines, according to their preliminary studies.

“Although two doses of the vaccine may still offer protection against severe disease caused by the Omicron strain, it’s clear from these preliminary data that protection is improved with a third dose of our vaccine,” Pfizer CEO and chairman Albert Bourla said.

“Ensuring as many people as possible are fully vaccinated with the first two dose series and a booster remains the best course of action to prevent the spread of COVID-19,” Bourla noted.

The omicron variant was first detected last month in South Africa, and quickly prompted a number of countries to implement travel restrictions against southern African countries in hopes of curbing its spread. 

Early reports from sources including the Centers for Disease Control and Prevention (CDC) indicate that COVID-19 cases caused by the new variant are less severe than those caused by other strains of the virus.

But the CDC researchers warned that “even if most infections are mild, a highly transmissible variant could result in enough cases to overwhelm health systems.”