This is the ValueSet that contains all the codes in LIVD SARS CoV2 Test Codes (http://cts.nlm.nih.gov/fhir/ValueSet/2.16.840.1.113762.1.4.1114.9) and LOINCs identifying qualitative COVID lab tests (http://hl7.org/fhir/uv/shc-vaccination/ValueSet/lab-qualitative-test-covid). E.g. what you have to deal with if you get resources containing codes in either of them