Please see the CPG 2021-04-15 Meeting Minutes/Agenda - Cross-Group Projects - Confluence (hl7.org) for background. The group asked me to create an issue to document proper handling of non-vaccine CVX codes (scroll down to the bottom table). The CVX code system contains some terms that are really procedures, medications, or substances rather than immunizations. So we should probably recommend that implementers not use those non-vaccine CVX codes in US Core Immunization resources.

Many of those non-vaccine CVX codes are now inactive, however the problem is that patient charts contain historical data for those codes. For example we have received real world CCDs with Immunization section entries containing CVX codes 95 - 98 for tuberculosis skin tests. There is an open question as to whether those codes should be allowed in the US Core Procedure profile, or if implementers should be required to translate those into a different code system. Further discussion is needed.