Previous reports suggested that peripheral facial palsy (Bell) was a side effect of the COVID-19 vaccine mRNA BNT162b2 (Pfizer-BioNTech), but a recent case-control study from Israel found no significant association between this vaccine and the Risk of facial palsy. The study results were published in JAMA Otolaryngology-Head & Neck Surgery.
The results of this study appear “remarkable” according to the researchers, given that the first vaccination in Israel took place in mid-December 2020; more than 92% of the country’s population aged 50 and over had received their first dose by March 1, 2021. “Even with a small association between the vaccine and facial nerve palsy, a dramatic increase in the number of cases should have been detectable,” explained the study researchers.
The study included 37 patients (mean age 50.9 years; men 59.5%) who were admitted to an emergency department of a tertiary referral center in Israel from January 1 to February 28, 2021 with newly developed peripheral facial palsy out of 21 (56 , 7%) patients had received the COVID-19 vaccine BNT162b2. All patients were assigned to 74 control patients based on age, gender and admission date, who were admitted for reasons other than facial nerve palsy.
In the vaccinated group, the mean interval between vaccination and onset of paralysis was 9.3 days from the first dose and 14.0 days from the second dose. In the control group, 59.5% (n = 44) of the patients were vaccinated with BNT162b2. The adjusted odds ratio for exposure to the vaccine in patients with paralysis was 0.84 (95% CI 0.37-1.90; P = 0.67).
In a separate analysis, the study leaders found a similar intake volume for facial palsy in 2021 compared to the years between 2015 and 2020 (mean 26.8; median 27.5).
The limitations of this study included evaluating only new vaccine effects and the lack of long-term results for analysis. In addition, the results may not be transferable to other approved COVID-19 vaccines.
Ultimately, the study’s researchers concluded that “no association was found between recent vaccination with the BNT162b2 vaccine and the risk of facial palsy”.
Shemer A, Pras E, Einan-Lifshitz A, Dubinsky-Pertzov B, Hecht I. Association of COVID-19 Vaccination and Facial Palsy: A Case-Control Study. JAMA Otolaryngol Head and Neck Surgery. 2021; 147 (8): 739-743. doi: 10.1001 / jamaoto.2021.1259