During the phase III Pfizer-BioNTech and Moderna trials, seven cases of facial paralysis or Bell's palsy were reported in the vaccine groups (7 of 35,654), and one case was seen in the placebo groups (1 of 35,611). A causal relationship was not established, but the FDA recommended that vaccine recipients be monitored.
Following the documentation of a case of Bell's palsy associated with vaccination,1 we were contacted by patients and colleagues from Canada, Australia, Europe, the UK, and United Arab Emirates. Questions raised were whether mRNA vaccine recipients are at increased risk of developing Bell's palsy, and what to recommend to individuals with a history of Bell's palsy.
It is unclear whether the vaccine caused the outbreaks of Bell’s palsy, but Dr. Paul Offit, a member of the FDA’s Vaccines Advisory Committee who voted to approve the Pfizer preventative, said in an interview with CNBC that the condition should be monitored. “I’m not dismissing that yet,” he said.
Despite geographical and seasonal variations, generally agreed incidence of Bell's palsy is 15–30 cases each year per 100 000 population. Ozonoff and colleagues rightly state that the predicted 12-month (annual) incidence of Bell's palsy inferred from mRNA vaccine trials is higher than that reported during the 2-month observation period of these studies. They concluded that the observed incidence of Bell's palsy in the mRNA vaccine arms was 3·5 to seven times higher than expected in the general population. However, safety data were collected for participants with a median follow-up of 2 months after the second dose; therefore, the data refer to an overall observation period of approximately 12 weeks from dose one. Given this, and considering Bell's palsy as the possible outcome of individual doses, the observed incidence in the mRNA vaccine trials would be roughly 1·5 to three times higher than in the general population
The numerical imbalance reported with mRNA vaccine trials was not seen in the Oxford-AstraZeneca and Johnson & Johnson phase 3 studies using more traditional virus-based technology. Examination of adverse event data from the Yellow Card scheme in the UK and from the EU EudraVigilance database might help clarify this matter. As of March 21, the Yellow Card-reported frequency of facial paralysis or paresis and facial nerve disorder after any dose was close to 23 per million with the Pfizer-BioNTech vaccine and 13 per million with the Oxford-AstraZeneca vaccine. Excluding reports of facial paralysis cross-listed with a cerebrovascular accident, EudraVigilance data indicate a much higher frequency of facial paralysis after the Pfizer-BioNTech vaccine than after the Oxford-AstraZeneca vaccine (497 vs 56 cases or 13·6 vs 4·1 per million doses as of April 3). The risk of developing facial paralysis could be two to three times higher in individuals receiving mRNA vaccines than in those receiving traditional vaccines. These findings should be considered when selecting a vaccine for patients with a history of Bell's palsy.
People who have previously had GBS may receive a COVID-19 vaccine. To date, no cases of GBS have been reported following vaccination in participants in the mRNA COVID-19 vaccine clinical trials. One case of GBS was reported in a vaccinated participant in the Johnson & Johnson Janssen COVID-19 Vaccine clinical trial (compared to one GBS case among those who received placebo). With few exceptions, the independent Advisory Committee on Immunization Practices (ACIP) general best practice guidelines for immunization do not include a history of GBS as a precaution to vaccination with other vaccines.
People who have previously had Bell’s palsy may receive a COVID-19 vaccine. Cases of Bell’s palsy were reported following vaccination in participants in the COVID-19 vaccine clinical trials. However, the Food and Drug Administration (FDA) does not consider these to be more than the rate expected in the general population. They have not concluded these cases were caused by vaccination.
