This is the ValueSet that contains all the codes in ActRelationshipPassiveImmunizationAgainst (http://terminology.hl7.org/ValueSet/v3-ActRelationshipPassiveImmunizationAgainst) and ActRelationshipPassiveImmunizationAgainst (http://terminology.hl7.org/ValueSet/v3-ActRelationshipPassiveImmunizationAgainst). E.g. what you have to deal with if you get resources containing codes in either of them