Participants are eligible to be included in the study only if all of the following criteria apply: High-risk cohort: 1. Men or women 18-80 years, inclusive, at the time of signing the informed consent 2. Willing and able to provide informed consent 3. Laboratory confirmed SARS-CoV-2 infection, with test results within past 72 hours 4. At increased risk of developing severe COVID-19 disease (at least one of the following) • Age =60 • Presence of pulmonary disease, specifically moderate or severe persistent asthma, chronic obstructive pulmonary disease (COPD), pulmonary hypertension, emphysema, or tuberculosis on treatment • Diabetes mellitus (type 1 or type 2), requiring oral medication or insulin for treatment • Hypertension, requiring at least 1 antihypertensive oral medication for treatment • Coronary artery disease with history of graft or stent • Cardiac failure, Class 2 or greater using New York Heart Association functional class • History of organ or stem cell transplant • Immunocompromised status due to disease (e.g., those living with human immunodeficiency virus, confirmed malignancy) • Immunocompromised status due to medication (e.g., persons taking 20 mg or more of prednisone equivalents a day, anti-inflammatory monoclonal antibody therapies, or cancer therapies) • Body mass index = 30 kg/m2

Participants are eligible to be included in the study only if all of the following criteria apply: High-risk cohort: 1. Men or women 18-80 years, inclusive, at the time of signing the informed consent 2. Willing and able to provide informed consent 3. Laboratory confirmed SARS-CoV-2 infection, with test results within past 72 hours 4. At increased risk of developing severe COVID-19 disease (at least one of the following) • Age =60 • Presence of pulmonary disease, specifically moderate or severe persistent asthma, chronic obstructive pulmonary disease (COPD), pulmonary hypertension, emphysema, or tuberculosis on treatment • Diabetes mellitus (type 1 or type 2), requiring oral medication or insulin for treatment • Hypertension, requiring at least 1 antihypertensive oral medication for treatment • Coronary artery disease with history of graft or stent • Cardiac failure, Class 2 or greater using New York Heart Association functional class • History of organ or stem cell transplant • Immunocompromised status due to disease (e.g., those living with human immunodeficiency virus, confirmed malignancy) • Immunocompromised status due to medication (e.g., persons taking 20 mg or more of prednisone equivalents a day, anti-inflammatory monoclonal antibody therapies, or cancer therapies) • Body mass index = 30 kg/m2