This case-sensitive code system http://terminology.hl7.org/CodeSystem/immunization-recommendation-status defines the following codes:

CodeDisplayDefinition
due DueThe patient is due for their next vaccination.
overdue OverdueThe patient is considered overdue for their next vaccination.
immune ImmuneThe patient is immune to the target disease and further immunization against the disease is not likely to provide benefit.
contraindicated ContraindicatedThe patient is contraindicated for futher doses.
complete CompleteThe patient is fully protected and no further doses are recommended.
 <status value="draft"/> <experimental value="false"/> <date value="2024-03-04T19:03:28+00:00"/> <publisher value="Health Level Seven International"/> <contact> <telecom> <system value="url"/> <value value="http://hl7.org"/> </telecom> <telecom> <system value="email"/> <value value="hq@HL7.org"/> </telecom> </contact> <description value="The value set to instantiate this attribute should be drawn from a terminologically robust code system that consists of or contains concepts to support describing the status of the patient towards perceived immunity against a vaccine preventable disease. This value set is provided as a suggestive example."/> <copyright value="This material derives from the HL7 Terminology (THO). THO is copyright ©1989+ Health Level Seven International and is made available under the CC0 designation. For more licensing information see: https://terminology.hl7.org/license"/> <caseSensitive value="true"/> <valueSet value="http://terminology.hl7.org/ValueSet/immunization-recommendation-status"/> <content value="complete"/> <concept> <code value="due"/> <display value="Due"/> <definition value="The patient is due for their next vaccination."/> </concept> <concept> <code value="overdue"/> <display value="Overdue"/> <definition value="The patient is considered overdue for their next vaccination."/> </concept> <concept> <code value="immune"/> <display value="Immune"/> <definition value="The patient is immune to the target disease and further immunization against the disease is not likely to provide benefit."/> </concept> <concept> <code value="contraindicated"/> <display value="Contraindicated"/> <definition value="The patient is contraindicated for futher doses."/> </concept> <concept> <code value="complete"/> <display value="Complete"/> <definition value="The patient is fully protected and no further doses are recommended."/> </concept> </CodeSystem>