Risk of disease relapse following COVID-19 vaccination in patients with AQP4-IgG-positive NMOSD and MOGAD

•We studied 56 patients with AQP4-IgG+NMOSD (n = 26) or MOGAD (n = 30) who received at least one dose of SARS-CoV-2 vaccination (mRNA-based).•Disease relapses within 1 month of vaccination occurred in only one patient with AQP4-IgG+NMOSD (4%).•The frequency of disease relapses was higher in patients who contracted SARS-CoV-2 infection before the vaccine (20%; 1/5).•In patients with AQP4-IgG+NMOSD or MOGAD the benefits of SARS-CoV-2 vaccination outweigh the risk of potential disease reactivation.