This is the ValueSet that contains all the codes in US Core Vaccine Administered Value Set (CVX) (http://hl7.org/fhir/us/core/ValueSet/us-core-vaccines-cvx) and CVX Vaccines Administered Vaccine Set (http://cts.nlm.nih.gov/fhir/ValueSet/2.16.840.1.113762.1.4.1010.6). E.g. what you have to deal with if you get resources containing codes in either of them