Vaccine Bell Palsy

About Vaccine Bell Palsy

Bell palsy, temporary facial paralysis, was observed during COVID vaccine trials. The FDA called for continued monitoring after a small number of additional cases were seen in vaccine compared to placebo groups. Post authorization surveillance generally found rates close to the expected background rate and did not establish a clear association. Bell palsy occurs at a rate of tens of cases per 100,000 people annually regardless of vaccination. Other vaccines have been investigated for Bell palsy associations with inconclusive results. The case illustrates how clinical trials with tens of thousands of participants can detect rare events that may or may not be causal. Careful surveillance is needed to distinguish real safety signals from coincidental events.