The Centers for Disease Control and Prevention (CDC) has announced that it will be investigating a possible safety concern for ischemic stroke in people ages 65 and older who received the Pfizer-BioNTech COVID-19 vaccine.
“Following the availability and use of the updated (bivalent) COVID-19 vaccines, CDC’s Vaccine Safety Datalink (VSD), a near real-time surveillance system, met the statistical criteria to prompt additional investigation into whether there was a safety concern for ischemic stroke in people ages 65 and older who received the Pfizer-BioNTech COVID-19 vaccine, bivalent,” the CDC stated in a release. “Rapid-response investigation of the signal in the VSD raised a question of whether people 65 and older who have received the Pfizer-BioNTech COVID-19 Vaccine, Bivalent were more likely to have an ischemic stroke in the 21 days following vaccination compared with days 22-44 following vaccination.”
Fortunately, to date, the CDC reports that no other safety systems have shown a similar signal and multiple subsequent analyses have not validated this signal:
- A large study of updated (bivalent) vaccines (from Pfizer-BioNTech and Moderna) using the Centers for Medicare and Medicaid Services database revealed no increased risk of ischemic stroke.
- A preliminary study using the Veterans Affairs database did not indicate an increased risk of ischemic stroke following an updated (bivalent) vaccine.
- The Vaccine Adverse Event Reporting System (VAERS) managed by CDC and FDA has not seen an increase in reporting of ischemic strokes following the updated (bivalent) vaccine.
- Pfizer-BioNTech’s global safety database has not indicated a signal for ischemic stroke with the updated (bivalent) vaccine.
- Other countries have not observed an increased risk for ischemic stroke with updated (bivalent) vaccines.
Although the totality of the data currently suggests an unlikelihood that the signal in VSD represents a true clinical risk, the CDC and FDA will continue to evaluate additional data from these and other vaccine safety systems.
Neither the CDC nor Food and Drug Administration (FDA) have detected a potential risk stemming from the Moderna COVID-19 vaccine, bivalent as of now.
Despite the investigation, the CDC is still recommending for everyone six months of age and older to stay up-to-date with COVID-19 vaccination. For information on vaccination in Mississippi, click here.
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