The effectiveness of Pfizer/BioNTech’s corona vaccine drops to 84 percent after six months. At its peak, the efficacy is 96 percent.
Researchers write this in a pre-publication of their research, in which more than 44,000 volunteers worldwide participate.
The vaccine works best in the first two months after the second and last shot. Then it slowly decreases. The scientists write that despite the decrease in effectiveness, the vaccine is still safe after six months and can prevent Covid-19 very well. The drug protects 97 percent against severe disease, the study says.
The international study has not yet received a so-called peer review, which means that other independent scientists have not yet assessed the results. 32 researchers from seventeen parties were involved in the development, including universities, hospitals, research centres, Pfizer and BioNTech.
The Pfizer/BioNTech vaccine consists of two doses administered at different times. According to Pfizer, it’s likely that fully vaccinated people will need a third shot within 12 months to keep them well protected. A possible repeat shot is also taken into account with the other corona vaccines.
