Inclusion Criteria:  Children between 1 to 15 years of age Willing to provide informed consent (parents)/assent For Group 1 - Positive or Negative for COVID-19 by RT-PCR but positive for SARS-CoV2 IgG For Group 2 - Positive for COVID-19 by RT-PCR but negative for SARS-CoV2 IgG For Group 3 - Positive for COVID-19 by RT-PCR or positive for SARS-CoV2 IgG antibody For Group 4 - Control children who are negative for both RT-PCR and IgG antibody  Exclusion Criteria:  Severely immunocompromised or anemic (WHO criteria in children) or malnourished History of any illness or condition which, in the investigator's judgment, may substantially increase the risk associated with the participant's participation in the protocol, or compromise the scientific objectives