Israeli Study Proves Third Dose Of COVID-19 Vaccine Boosts Immunity

Illustration of COVID-19 vaccination in Israel. (Wikimedia Commons/Amos Ben Gershom/Israel Government Press Office)

JAKARTA - The third dose of Pfizer's COVID-19 vaccine significantly increased protection from serious infections and illnesses among people aged 60 and older in Israel compared to those who received two injections, according to findings published by the Ministry of Health on Sunday.

The data was presented at a meeting of the ministry's panel of vaccination experts on Thursday last week and uploaded to its website yesterday, although full details of the study were not released.

The findings are on par with separate statistics reported last week by health care provider Maccabi Israel, one of several organizations giving booster shots to try to curb the Delta variant of the coronavirus.

Detailing statistics from Israel's Gertner Institute and the KI Institute, ministry officials said that among people aged 60 years and over, the protection against infection given from 10 days after the third dose was four times higher than after two doses.

The third dose for over 60 years offers five to six times greater protection, after 10 days with respect to serious illness and hospitalization. This age group is particularly vulnerable to COVID-19. In Israel, they were the first to receive the vaccine when the COVID-19 vaccination program began in late December.

In recent weeks, the Health Ministry said immunity had been reduced over time for the elderly and young people as well. Most vaccinated people who fall seriously ill in Israel are over the age of 60 and with underlying health conditions.

Israel began giving its third injection in more than 60 years on 30 July. On Thursday, local authorities lowered the age of eligibility for boosters to 40 and included pregnant women, teachers, and health workers under that age. The third dose is only given to those who received the second injection at least five months ago.

Separately, the United States has announced plans to offer booster injections to all its citizens, citing data showing diminishing protection. Canada, France, and Germany have announced booster campaigns.

Fighting an outbreak of the Delta variant since June, Israel currently has one of the highest infection rates per capita in the world. Nearly 1.5 million people out of the country's 9.3 million population have received a third blow.

A separate study by Tel Aviv's Sourasky Medical Center found that immunosuppressed individuals under the age of 65 developed 43 percent more antibodies after receiving their third shot of Pfizer's coronavirus vaccine than they did after their second shot. Meanwhile, for those over the age of 65, there was an increase of 36 percent.

In addition, Health Ministry Director-General Nachman Ash said the third dose is expected to have a more lasting effect than the previous two, possibly at least nine to 12 months.

"The data are very encouraging", said Prof. Cyrille Cohen, head of the immunology laboratory at Bar-Ilan University, quoted The Jerusalem Post.

"We know the effectiveness of vaccines decreases over time and therefore the more (antibodies) you start, the longer the protection may be effective".