Onset of various CNS inflammatory demyelination diseases following COVID-19 vaccinations.

BACKGROUND: Since the start of COVID-19 vaccination worldwide, there have been several reports of inflammatory demyelinating diseases of the central nervous system (CNS-IDDs) following vaccination. METHODS: We prospectively collected cases of new-onset CNS-IDDs with a temporal relationship between disease onset and COVID-19 vaccination and investigated their proportion among newly registered cases of CNS-IDD over the past year. RESULTS: Among 117 cases, 10 (8.5%) had their first disease manifestation within one month following COVID-19 vaccination: 2 multiple sclerosis, 2 neuromyelitis optica spectrum disorder, 3 MOG antibody-associated disease, and 3 unclassified CNS-IDDs. CONCLUSION: This observation suggests that COVID-19 vaccination may trigger the onset of various CNS-IDDs in susceptible individuals.