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

Post-vaccination disease relapses have been reported in patients with MOGAD and AQP4-IgG+NMOSD. In this retrospective multicenter Italian study we assessed the frequency of relapses after SARS-CoV-2 vaccination. We included 56 cases: MOGAD, 30; AQP4-IgG+NMOSD, 26. Vaccines received were BNT162b2-Pfizer-BioNTech in 42 patients and mRNA-1273-Moderna in 14 patients. Six patients had a history of SARS-CoV-2 infection; two of them experienced a post-infection disease relapse (MOGAD). The frequency of relapses within one month of SARS-CoV-2 vaccination was 4% (1/26) in the AQP4-IgG+NMOSD group and 0% in the MOGAD group. In these patients the potential benefits of vaccination overcome the risk of relapses.