On October 4, a study was published in the English medical journal The Lancet that looked at the extent to which the efficacy of the Pfizer vaccine decreased over time that could be attributed to poor immune protection and at the expense of the delta variable.
In a retrospective cohort study, data from health care provider Kaiser Permanente in Southern California were evaluated for nearly 3.5 million people, with an average age of 45 years.
After administration of the full series of vaccines, the effectiveness of protection against infection was 73 percent and the effectiveness of protection against hospital referrals was 90 percent. Efficacy drops to 47 percent five months after the first month (88 percent) – Zappulex Dobson explains research results on the coronavirus vaccine Facebook page Professional pharmacist.
Vaccine efficacy against the delta variant was 93 percent in the first month after two doses, but dropped to 53 percent after 4 months. But the Hospital treatment Protection against the delta variant remained 93 percent in all age groups up to 6 months.
Thus, this study shows that the Pfizer vaccine is highly effective against 6-month hospitalization, even in the delta variant.
The expert confirms.
It is assumed that the decrease in efficacy is not primarily due to the delta variant, but to a decrease in immunity over time since the second vaccination.
More details It can be read here.