A Study to Assess the Potential Impact of Disease Modifying Therapies on COVID-19 Outcomes and the Antibody Response Following an Infection With SARS-CoV-2 in Patients With Multiple Sclerosis Within the Swiss Multiple Sclerosis Cohort.

clinical data collection regarding COVID-19 suggestive symptoms or confirmed SARS-CoV-2-infections (medical events), recorded comorbidities (concomitant diseases relevant to MS and COVID-19) and recorded vaccinations (other treatments). This information is systematically collected during the routine clinical visits of the patient within the SMSC every 6-12 months.

analysis of archived serum samples collected every 6-12 months within the SMSC for measurement of anti-SARS-CoV-2 antibodies in pre-pandemic reference samples and prospectively determine the anti-SARS-CoV-2-serostatus during the study period.