multiple sclerosis(258) COVID-19(249) Patient(214) Multiple(166) SARS-CoV-2(157) vaccination(121) disease(119) Treatment(116) therapy(111) patients(104) treated(101) humoral(90) antibody(87) age(86) Vaccine(82) Infection(77) patients treated(65) Ocrelizumab(64) B-cell(64) receiving(63) Humoral response(58) COVID-19 infection(58) dose(58) SARS-COV-2 infection(58) positive(56) anti-CD20(55) outcome(55) risk(53) vaccination.(50) reported(49)