According to a study conducted by the Maccabi Healthcare Services, immunity appears to further strengthen even after seven days from the second injection.
New data released by the Maccabi Healthcare Services has confirmed the effectiveness of the Pfizer coronavirus vaccine.
As of Thursday, only 254 individuals out of the 416,900 who were already a week after the second Pfizer shot – the time where the immunity is considered to kick in – got infected with the virus, the organization reported. Moreover, those who were found to be positive only had light symptoms, with just four of them being hospitalized, all of them in light condition.
Over the same period of time, some 12,944 new cases of COVID-19 emerged in the control group of some 778,000 people having a diverse health profile.
A comparison between the data from the two groups shows that the vaccine is 91% effective seven days or more after the second injection is administered.
From a segmentation of the infections that did occur, it appears that the immunity increases as the days go by. Among the 254 people who contracted the virus, 76 of them were infected after seven days, 44 on the eight day, and 24 on the ninth day. Between day 22 and 24 – when the test period ended – no one was infected.
According to the studies conducted by Pfizer, the vaccine had an efficacy of about 95%, which is considered very high.
With some 2.5 million members, Maccabi is the second largest health fund in Israel. About 900,000 of its customers have already received the first shot, and about 500,000 the second one.
“The data continue to be very encouraging and to show that the effectiveness of the vaccine is high and stable,” Dr. Anat Aka Zohar, head of Maccabi’s Information and Digital Health Division said. “The findings clearly indicate that as the days go by after the second dose, the immunity becomes stronger.”
She also emphasized that the vaccine does not only protect against infection but also again developing more severe symptoms.