Possible Safety Concern With New Pfizer COVID-19 Vaccine Identified: CDC

A vial of Pfizer's COVID-19 vaccine in Seattle on June 21, 2022. David Ryder/Getty Images

Data indicates Pfizer’s new COVID-19 vaccine could cause a type of stroke in elderly people, two U.S. health agencies said on Jan. 13.

The threshold for a safety signal was met for Pfizer’s bivalent booster in the Vaccine Safety Datalink, a monitoring system run by the U.S. Centers for Disease Control and Prevention (CDC).