Study on Long-term Effects of COVID-19 Infection

Inclusion Criteria: 1. Willing and able to provide written informed consent, and 2. Age \>/= 18 years, and 3. A history of SARS-CoV-2 infection, as evidenced by: 1. Available laboratory documentation of SARS-CoV-2 RNA positivity on a nucleic acid amplification test or by serologic testing when this becomes available, or 2. Reference by the participant to a laboratory test performed on respiratory tract secretions or blood, fingerstick, or saliva test that was reported to the participant to be positive for SARS-CoV-2 or COVID-19 infection, 4. And a period of 21 days or more has elapsed since the first positive test or symptoms preceding the first positive test, whichever is earlier. Exclusion Criteria: 1. Self-reported or documented chronic anemia with hemoglobin \< 9 g/dL. Anemia during a preceding acute illness will not be exclusionary. 2. Serious medical or psychiatric illness that, in the opinion of the site investigator, would interfere with the ability to adhere to study requirements or to give informed consent. 3. Active drug or alcohol use or dependence that, in the opinion of the Principal Investigator, would interfere with adherence to study requirements or to give informed consent.