BACKGROUND AND PURPOSE: 

• Peripheral facial nerve (Bell’s) palsy has been reported and widely suggested as a possible adverse effect of the Pfizer-BioNTech COVID-19 vaccine 
• Shemer et al. (JAMA Otolaryngology Head Neck Surgery, 2021), assessed whether COVID-19 mRNA vaccination was associated with facial nerve palsy in a case-control study 

METHODS: 

• Case-control study 
• Setting 
  • Israel 
• Population 
  • Patients admitted for facial nerve palsy matched with control patients by age, sex, and date of admission 
• Exposures 
  • Recent COVID-19 vaccination with Pfizer-BioNTech  
• Primary outcomes 
  • Odds of facial nerve palsy with vaccination 

RESULTS: 

Case-control study 

• 37 patients with facial nerve palsy (74 matched controls) 
  • 59.5% male | Mean (SD) age 50.9 (20.2) 
  • Recently vaccinated: 56.7% 
• Facial nerve palsy onset among vaccinated patients  
  • Mean (SD) time from first dose: 9.3 (4.2) days (range 3 to 14) 
  • Mean (SD) time from second dose: 14.0 (12.6) days (range 1 to 23)  
• There were no increased odds of vaccination exposure among those with facial nerve palsy 
  • Adjusted odds ratio 0.84 (95% CI, 0.37 to 1.90); P=0.67 
• Analysis of the number of admissions for facial nerve palsy during the same period in preceding years (2015-2020)  
  • Stable trend with no increase in facial nerve palsy admission  

CONCLUSION: 

• No association was found between COVID-19 vaccination with mRNA COVID-19 vaccines and risk for facial nerve palsy 
• Another study by Renoud et al. (JAMA Intern Med, 2021) also explored this potential adverse event through a disproportionality analysis 
  • 133,883 cases of adverse drug reaction in mRNA COVID-19 pharmacovigilance database  
  • Cases of facial paralysis: 0.6% (844 patients)  
  • No signal of disproportionality of facial paralysis vs other vaccines or influenza vaccine specifically  
  • Risk is very low, and no higher when compared to other viral vaccines 
• Shemer et al. conclude

In this case-control study, no association between acute facial nerve palsy and recent vaccination with the BNT162b2 vaccine was observed 

In addition, despite rapid and extensive vaccination of the population, a similar volume of admissions for facial nerve palsy was seen compared with the same period in preceding years 

Learn More – Primary Sources: 

Association of COVID-19 Vaccination and Facial Nerve Palsy: A Case-Control Study 

Association of Facial Paralysis With mRNA COVID-19 Vaccines: A Disproportionality Analysis Using the World Health Organization Pharmacovigilance Database 

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