private Immunization BuildImmunization( Visit visit,
                                          ActivityType activityType, CodedConcept vaccineCodedConcept )
 {
     var immunization = new Immunization ( visit, activityType );
     immunization.ReviseImmunizationVaccineInfo(new ImmunizationVaccineInfo(vaccineCodedConcept, null, new ImmunizationVaccineManufacturer(null, null)));
     Session.SaveOrUpdate ( immunization );
     return immunization;
 }