This value set includes codes based on the following rules:

• Include these codes as defined in http://snomed.info/sct version http://snomed.info/sct/731000124108/version/20200901

  Code	Display
  277057000	Community contact with a known COVID-19 case

• Include these codes as defined in urn:oid:2.16.840.1.114222.4.5.274 version 20200526

  Code	Display
  PHC2268	Healthcare-associated contact (patient, visitor, or healthcare worker)
  PHC2127	Household contact with a known COVID-19 case

• Include these codes as defined in http://terminology.hl7.org/CodeSystem/v3-NullFlavor version 20090501

  Code	Display
  OTH	Other (specify)
  UNK	Unknown