inclusion criteria: an individual aged <21 years presenting with fever (>38.0°c for ≥24 hours; may be by subjective report) and two or more of the following (from two different systems; e.g. one from cardiac and one from mucocutaneous): cardiac hypotension shock arrhythmia tachycardia left ventricular ejection fraction <55% valvulitis coronary artery enlargement (lad or rca z-score ≥ 2.5) pericardial effusion gastrointestinal diarrhea nausea/vomiting significant abdominal pain immunologic lymphadenopathy (unilateral cervical or diffuse) mucocutaneous bilateral conjunctival injection extremity swelling or erythema rash lip erythema/strawberry tongue neurologic altered mental status focal neurological deficits headache meningismus laboratory evidence of inflammation, including but not limited to, an elevated c-reactive protein (crp), erythrocyte sedimentation rate (esr), fibrinogen, procalcitonin, d-dimer, ferritin, lactic acid dehydrogenase (ldh), neutrophilia, lymphopenia or hypoalbuminemia and no alternative plausible diagnoses based on clinical judgement and positive for current or recent sars-cov-2 infection by rt-pcr, serology, or antigen test; or suspected covid-19 exposure and parent or legal guardian (or self if at least 18 years old) able and willing to provide informed consent and subject willing and able to provide assent when appropriate.

inclusion criteria: an individual aged <21 years presenting with fever (>38.0°c for ≥24 hours; may be by subjective report) and two or more of the following (from two different systems; e.g. one from cardiac and one from mucocutaneous): cardiac hypotension shock arrhythmia tachycardia left ventricular ejection fraction <55% valvulitis coronary artery enlargement (lad or rca z-score ≥ 2.5) pericardial effusion gastrointestinal diarrhea nausea/vomiting significant abdominal pain immunologic lymphadenopathy (unilateral cervical or diffuse) mucocutaneous bilateral conjunctival injection extremity swelling or erythema rash lip erythema/strawberry tongue neurologic altered mental status focal neurological deficits headache meningismus laboratory evidence of inflammation, including but not limited to, an elevated c-reactive protein (crp), erythrocyte sedimentation rate (esr), fibrinogen, procalcitonin, d-dimer, ferritin, lactic acid dehydrogenase (ldh), neutrophilia, lymphopenia or hypoalbuminemia and no alternative plausible diagnoses based on clinical judgement and positive for current or recent sars-cov-2 infection by rt-pcr, serology, or antigen test; or suspected covid-19 exposure and parent or legal guardian (or self if at least 18 years old) able and willing to provide informed consent and subject willing and able to provide assent when appropriate.