Estimating Prevalence of COVID-19 Infection and SARS-CoV-2 Antibodies in MS Patients

Inclusion Criteria (Part A and B): ● Patient is outside of infectious period of COVID-19 defined as follows: * Patient with mild to moderate illness who are not severely immunocompromised: * At least 10 days have passed since symptoms first appeared and * At least 24 hours have passed since last fever without the use of fever-reducing medications and * Symptoms (e.g. cough, shortness of breath) have improved * Patient with severe to critical illness or who are severely immunocompromised: * At least 10 days and up to 20 days have passed since symptoms first appeared * At least 24 hours have passed since last fever without the use of fever-reducing medications and * Symptoms (e.g. cough, shortness of breath) have improved * Clinician-diagnosed MS treated or untreated with an approved DMT, * Ages 18 to 60, * EDSS 0 - 7, * Able to give informed consent, * Able to complete, or have someone help complete the patient questionnaire, * No high dose steroids, or IVIG, or PLEX use within 3 months of blood sample, * No convalescent plasma and/or polyclonal antibody treatments for COVID-19 within 3 months of blood sample collection. Inclusion Criteria (Part B only) * COVID-19 positive patients, who received OCR within 6 months of COVID 19 infection, * EDSS 0 - 6. Inclusion Critera (Redraws Only) * Completed standard of care COVID-19 vaccination series * On Ocrevus, glatiramer, interferon b, or not on any treatment disease-modifying treatment at the time of vaccination. Exclusion Criteria (Part A and B): * Concurrent immunosuppressive therapy, active systemic cancer, primary or acquired immunodeficiency (i.e., CVID, HIV infection), * Active drug or alcohol abuse, * Other anti-CD20 therapy apart from OCR, * Uncontrolled diabetes mellitus, * End-organ failure (cardiac, pulmonary, renal, hepatic), * Systemic lupus erythematosus (SLE). Exclusion Criteria (Part B only): * EDSS \>6, * Active infection (e.g., hepatitis). Exclusion Criteria (Healthy Controls Sample) * Concurrent immunosuppressive therapy, active systemic cancer, primary or acquired immunodeficiency (e.g. CVID, HIV infection), * Active ongoing drug or alcohol abuse, * Age \>60 or \<18, * Uncontrolled diabetes mellitus, * End-organ failure (cardiac, pulmonary, renal, hepatic), * SLE * No high dose steroids, or intravenous immunoglobulin (IVIG) or plasma exchange (PLEX) use within 3 months of blood sample collection, * No convalescent plasma and/or polyclonal antibody treatments for COVID-19 within 3 months of blood sample collection.