A third dose of Pfizer’s coronavirus vaccine can make protection against the Delta variant up to 100 times more effective, according to data released on Wednesday by the American company.
It indicates in particular that after the third dose of the vaccine the number of antibodies was more than five times higher in people aged 18 to 55 and more than 11 times higher in people aged 65 to 85, according to studies.
Israel is investigating
As debate arises over the need for a third dose, Israel has embarked on its own studies.
“There are no precise data on the effectiveness of the third vaccine anywhere in the world. But Israel was the first country to get vaccinated very early. And now the number of antibodies is dropping. That is why we will have to make the decision on the third vaccine based on our own research, ”Prof. Arnon Afek from Sheba Medical Center and Acting Director of Tel HaShomer Hospital told Sputnik.
The study by the Israeli researchers will be carried out in three stages on different age groups, taking into account the state of health of the patients.
“For now, we are giving a third vaccine to people who are most at risk. These are people who have immune problems, like people who have organs transplanted. We do all of this with care, monitoring and recording the data. In the next step, we will start giving the very old people a third injection of the vaccine. The next step could be the vaccination of our own caregivers who agreed to participate in the study, ”said the professor.
As a reminder, Israel has managed to conduct one of the most effective vaccination campaigns in the world, with around 57% of its population fully vaccinated. 61.6% received a first dose since December 20, 2020. But, with the arrival of the Delta variant, there has been an increase in infections.
More than 2,000 cases of coronavirus infection were recorded in Israel in 24 hours on July 27 for the first time since March, according to the country’s health ministry.
Studies on the effectiveness of the Pfizer vaccine
A study on the effectiveness of the Pfizer vaccine concluded that, for six months, its effectiveness was 91%. Every two months, the effectiveness of the preparation in preventing infection with the novel coronavirus, causing even minor symptoms, decreased by 6% on average. An efficacy rate of 96% was recorded within two months of vaccination and was reduced to 84% six months later. A pre-publication of this study was posted on July 27 on the medRxiv website.
More than 44,000 volunteers participated in this research. The prepublication states that if the efficacy of the vaccine declines over time at the rate described in the article the efficacy of the preparation will be less than 50% within 18 months of vaccination. In this case, repeat vaccination will be necessary.
Also according to the study, the vaccine’s effectiveness in preventing a severe form of the disease was 97%.
Another study relayed by the New England Journal of Medicine finds that two doses of the Pfizer-BioNTech vaccine offer 88% protection against the Delta variant, against nearly 94% for the Alpha variant, said British.