Pediatric COVID Outcomes Study (PECOS)

This study will establish a cohort of surviving pediatric patients with symptomatic (including COVID-19 and MIS-C) and asymptomatic SARS-CoV-2 infection to study the long-term sequelae of acute infection and the evolution of the immune response over time. Longitudinal follow-up of this cohort will provide important information about clinical sequelae of acute COVID-19 and MIS-C, characteristics of the immune response to SARS-CoV-2, genetic factors associated with long-term outcomes, and the extent and duration of protective immunity. The study procedures include: 1. Non-contrast chest computed tomography (CT) or chest X-ray: All participants will undergo 2 chest imaging procedures, one at baseline and one at the final study visit (year 3). 2. Non-contrast cardiac magnetic resonance imaging (MRI): All participants will undergo 2 to 3 non-contrast cardiac MRI procedures during this study. 3. Echocardiogram 4. Electrocardiography (EKG) 5. Pulmonary Function Test (PFT) 6. Questionnaires: To complete the questionnaires will take approximately 25 to 64 minutes. 7. Collection of blood (including for optional genetic testing), nasopharyngeal (NP) swab, urine, and stool. Genetic testing (optional): This protocol involves genetic testing using whole genome sequencing (WGS) approaches for all participants. Clinical photography (optional): Participants may decline photographs or place any restrictions on their use.