Agency emphasizes that risk is unlikely and continues to recommend vaccinations.
January 15, 2023 – The US Centers for Disease Control and Prevention (CDC) has announced that there may be a possible safety issue with the bivalent COVID-19 vaccine made by Pfizer and BioNTech, specifically an increased risk of ischemic strokes in people 65 and older who recently received the updated booster shot.
However, the agency has emphasized that this risk is unlikely to be a true concern and continues to recommend that people stay up-to-date with Covid-19 vaccines.
The CDC’s Vaccine Safety Datalink (VSD) detected the possible increase, but the agency has identified possible confounding factors in the data from the VSD that may be biasing the data and require further investigation.
The CDC has also stated that it has not found the same increase in strokes in other large collections of medical records, such as those maintained by Medicare, the US Department of Veterans Affairs, and its Vaccine Adverse Event Reporting System (VAERS), and neither Pfizer nor other countries using the vaccine have seen any increase in this kind of stroke.
Despite this, the CDC is conducting further analysis and will discuss the issue at the upcoming January 26 meeting of the FDA’s Vaccines and Related Biological Products Advisory Committee. Pfizer and BioNTech have also stated that they have not observed similar findings across numerous other monitoring systems in the US and globally, and there is no evidence to conclude that ischemic stroke is associated with the use of their COVID-19 vaccines.
It is worth mentioning that the same safety signal has not been detected with the bivalent Moderna booster, and the CDC has also looked for and failed to find the same increase in strokes in other large collections of medical records.
The CDC does not recommend any change to vaccination practices at this time and that the risks of COVID-19 for older adults continue to outweigh any possible safety issues with the vaccine.