Bell’s Palsy, Other Rare Events Not Linked With COVID-19 Vaccines

Immune-mediated neurologic events did not increase after COVID-19 vaccination, electronic health record data in the U.K. and Spain showed.

No safety signal was found between COVID-19 vaccines and Bell’s palsy, encephalomyelitis, Guillain-Barré syndrome, or transverse myelitis, reported Daniel Prieto-Alhambra, MD, PhD, of the University of Oxford in England, and co-authors.

However, rates of Bell’s palsy, encephalomyelitis, and Guillain-Barré syndrome were higher than expected after COVID-19 infection, the researchers wrote in The BMJ.

“Spontaneous reports of Guillain-Barré and other immune-mediated neurological conditions led to the investigation of these as potential side effects associated with some COVID vaccines,” Prieto-Alhambra told MedPage Today.

“We wanted to research this using clinical data from well-curated data sources,” he said. “In addition, we wanted to investigate if an association exists with COVID-19, as some previous research has suggested that viral infections can cause or trigger similar conditions.”

Both the FDA and the European Medicines Agency have listed Guillain-Barré syndrome, an acquired demyelinating polyneuropathy, as a very rare side effect of viral vector vaccines. Bell’s palsy, a facial nerve paralysis, has been shown to be more common in people with SARS-CoV-2 infection than in people vaccinated against the virus.

An earlier epidemiology study in England demonstrated that neurologic events were more common overall after a positive SARS-CoV-2 test than after vaccination, noted Anton Pottegård, DMSc, PhD, of the University of Southern Denmark in Odense, and Olaf Klungel, MSc, PhD, of Utrecht University in the Netherlands, in an accompanying editorial.

“Importantly, all risks — even those observed after SARS-CoV-2 infection — are small in absolute terms for the single individual,” the editorialists wrote. “Even small absolute risks can, however, lead to a substantial burden on the healthcare system in the context of mass vaccination and widespread infection.”

The findings of the current study and the previous one in England “are reassuring about the safety of the vaccines, particularly compared with the observed risks associated with SARS-CoV-2 infection.”