SARS CoV-2 is the virus responsible for the pandemic COVID-19, which has resulted in nearly five million deaths worldwide since its spread in the beginning of 2020. In the United States, there are currently two emergency use authorized mRNA based vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Multiple sclerosis (MS) is a neurological autoimmune disease involving the central nervous system and requiring long-term immunomodulating therapy to control relapse and progression. While there are many approved medications for the treatment of MS, agents that work through B-lymphocyte depletion or sequestration are among the commonly used treatments. There is concern that individuals with low levels of circulating B-cells might not mount an effective humoral or cellular immune response after vaccination. Moreover, it remains to be understood whether, at certain timepoints within the treatment cycle, there is a greater immune response mounted while on B-cell depleting medication. Availability of such knowledge could guide counseling and management of patients on immunomodulatory therapy. Aim: To ascertain efficacy of mRNA based SARS CoV-2 vaccines in individuals with MS across the immunotherapy spectrum, via biomarker data of humoral and cellular immunity and via clinical data. Blood will be drawn for markers of immunity and sequence-based analysis before and after vaccination at predetermined time points. The investigators will document the type of immunotherapy being used at the time of vaccination. Clinical data on diagnosis of SARS-CoV2 infection will be collected at each of the prespecified timepoints.