Pfizer's COVID vaccine seems safe, effective 6 months laterVaccine effectiveness (VE) for the Pfizer/BioNTech COVID-19 vaccine against COVID-19 was 91% up to 6 months after the second dose, according to a non–peer-reviewed study published yesterday on the preprint server medRxiv.The researchers followed 44,060 people 16 and older, randomly assigning half to receive two doses of the Pfizer/BioNTech vaccine and half to a placebo.
Most of the 152 recruitment sites were in the United States (130), followed by Turkey (9), Germany (6), and South Africa (4).
The study also followed 2,260 US children 12 to 15 years old, with half receiving the intervention and half receiving placebo.VE was 91.1% up to 6 months after the second vaccine dose,