The third dose of the Pfizer/BioNTech’s coronavirus vaccine was 86 percent effective for people over 60 years old, Israeli health care provider Maccabi said on Wednesday.

Dr. Anat Ekka Zohar of Maccabi said the third dose “has again proved its effectiveness,” and had “demonstrated protection (against) the Delta variant,” reported Reuters.

Only 37 people tested positive after having the third shot compared to 1,064 who tested positive after only two doses, according to Maccabi.

Israeli Health Ministry data on Wednesday showed that per 100,000 people, there are 172 serious cases from unvaccinated people over 60 compared to 21 serious cases from the vaccinated, according to the report.