Recording immunization without vaccine

Good afternoon

I am modelling a situation where we want to record a history of a virus such as VZV where a patient is now immune to the virus, but has never had the vaccine.

Have any of you encountered and recorded this situation?

Thanks in advance.

Good question. The Immunization resource is for actual immunization events or the documentation of immunizations not given (typically refused by the patient). I would expect that the history of VZV infection would be documented elsewhere (a Condition for having had varicella or shingles, an Observation with serology test results, etc). It’s possible to create an immunization resource with a status of “not-done” and a statusReason code for something like “immune” or “history of disease”, but I might limit this to cases where a clinician has actively made the decision not to vaccine because of a history of disease rather than having a resource created by the system when a Condition or Observation is documented.