Inclusion Criteria:  Fluent in English or Spanish Age 18 years and over Test positive for SARS-CoV-2 (defined as a patient who reports receiving any screening or diagnostic test used to detect the presence of SARS-CoV-2 including any FDA-approved or authorized molecular or antigen-based assay) at least 2 months prior to the start of this study OR test positive for antibodies to SARS-CoV-2 at any point OR receive a positive T-test at any point OR receive a clinical diagnoses of COVID-19 at any point OR was hospitalized due to COVID-19 at any point Self-report moderate to severe symptoms or disability due to PASC Self-report planning to receive a vaccine against SARS-CoV-2 Self-report has not yet received any doses of a vaccine against SARS-CoV-2  Exclusion Criteria:  Unable to provide informed consent Unable to provide 3 blood and saliva samples at one of the 2 participating Yale New Haven Health blood draw sites on a Monday or Wednesday morning (before 12 pm). Does not have access to a hand-held device or computer that would allow for digital participation in the study Do not have and do not want to set up an email address Individuals who are prisoners