Global and regional burden of vaccine-associated facial paralysis, 1967–2023: findings from the WHO international pharmacovigilance database

The scarce and conflicting data on vaccine-associated facial paralysis  limit our understanding of vaccine safety on a global scale. Therefore,  this study aims to evaluate the global burden of vaccine-associated  facial paralysis and to identify the extent of its association with  individual vaccines, thereby contributing to the development of a more  effective vaccination program. We used data on vaccine-associated facial  paralysis from 1967 to 2023 (total reports, n = 131 255 418 418)  from the World Health Organization International Pharmacovigilance  Database. Global reporting counts, reported odds ratios (ROR), and  information components (ICs) were computed to elucidate the association  between the 16 vaccines and the occurrence of vaccine-associated facial  paralysis across 156 countries. We identified 26 197 reports (men, n = 10  507 [40.11%]) of vaccine-associated facial paralysis from 49 537  reports of all-cause facial paralysis. Vaccine-associated facial  paralysis has been consistently reported; however, a pronounced increase  in reported incidence has emerged after the onset of the coronavirus  disease 2019 (COVID-19) pandemic, which is attributable to the COVID-19  mRNA vaccine. Most vaccines were associated with facial paralysis, with  differing levels of association, except for tuberculosis vaccines.  COVID-19 mRNA vaccines had the highest association with facial paralysis  reports (ROR, 28.31 [95% confidence interval, 27.60–29.03]; IC, 3.37  [IC0.25, 3.35]), followed by encephalitis, influenza,  hepatitis A, papillomavirus, hepatitis B, typhoid, varicella-zoster,  meningococcal, Ad-5 vectored COVID-19, measles, mumps and rubella,  diphtheria, tetanus toxoids, pertussis, polio, and Hemophilus influenza  type b, pneumococcal, rotavirus diarrhea, and inactivated whole-virus  COVID-19 vaccines. Concerning age- and sex-specific risks,  vaccine-associated facial paralysis was more strongly associated with  older age groups and males. The serious adverse outcome and death rate  of vaccine-associated facial paralysis were extremely low (0.07% and  0.00%, respectively). An increase in vaccine-induced facial paralysis,  primarily owing to COVID-19 mRNA vaccines, was observed with most  vaccines, except tuberculosis vaccines. Given the higher association  observed in the older and male groups with vaccine-associated facial  paralysis, close monitoring of these demographics when administering  vaccines that are significantly associated with adverse reactions is  crucial.