The Centers for Disease Control and Prevention (CDC) and Food and Drug Administration (FDA) jointly announced Friday they had flagged a potential connection between Pfizer’s bivalent COVID-19 booster shot and an increased risk of stroke for seniors.
The CDC said it is still recommending the shot in a statement published Friday, explaining that despite the initial cause for concern, a further investigation of the data did not reveal an increased risk of stroke after getting the Pfizer booster. After the bivalent booster began being distributed, the CDC’s Vaccine Safety Datalink (VSD) flagged a possible increased risk of stroke in the first 21 days after receiving the shot compared to the 21 days thereafter.
Lots of false stories saying new data show Covid mRNA vaccines cause strokes, and the CDC & FDA agree.
None of that is true.
FDA said: “We looked at the totality of the evidence, & there are no concerns at this time this represents a true safety signal”https://t.co/MSivTzFWY5
— Sean Kennedy, MPH (@phealthsean) January 13, 2023
Out of 550,000 people aged 65 and older who received the bivalent booster, 130 had strokes within the first three weeks following the shot, the VSD found, The Washington Post reported. None of those individuals died, but the number triggered a deeper review of the data by health authorities to determine if a link was present.
“Although the totality of the data currently suggests that it is very unlikely that the signal in VSD represents a true clinical risk, we believe it is important to share this information with the public,” the agencies’ statement reads. “No change in vaccination practice is recommended.” Attempts to replicate the data through other methods and with other databases failed, and health officials in other countries did not report similar findings to the CDC and FDA.
The VSD contains healthcare data for 12 million people from about a dozen healthcare organizations, and allows the CDC to monitor for potential statistical signs of adverse vaccine effects in real time, the outlet reported. The system is designed to have a high level of sensitivity to err on the safe side of flagging potential risks. No such flag was made for Moderna’s bivalent COVID-19 booster. (RELATED: ‘Bloated Bureaucracy’: Omnibus Spending Bill Creates New ‘Pandemic Czar’ Office In White House)
Still, the announcement that a link was suspected at all is likely to damper already-tame demand for the bivalent COVID-19 boosters. Despite the Biden administration investing billions of dollars in the updated shots, which were made to better target prevalent Omicron strains of the virus, only 16% of Americans aged five and over have gotten an updated dose, according to the CDC.