WHO Immunization Implementation Guide
1.0.0 - release

WHO Immunization Implementation Guide, published by WHO. This guide is not an authorized publication; it is the continuous build for version 1.0.0 built by the FHIR (HL7® FHIR® Standard) CI Build. This version is based on the current content of https://github.com/WorldHealthOrganization/smart-immunizations/tree/132/merge and changes regularly. See the Directory of published versions

: IMMZ.D2.DT.Seasonal influenza - XML Representation

Draft as of 2026-03-31

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<PlanDefinition xmlns="http://hl7.org/fhir">
  <id value="IMMZD2DTSeasonalinfluenzaSeasonalInfluenza"/>
  <meta>
    <profile
             value="http://hl7.org/fhir/uv/cpg/StructureDefinition/cpg-recommendationdefinition"/>
    <profile
             value="http://hl7.org/fhir/uv/crmi/StructureDefinition/crmi-shareableplandefinition"/>
    <profile
             value="http://hl7.org/fhir/uv/crmi/StructureDefinition/crmi-publishableplandefinition"/>
  </meta>
  <text>
    <status value="extensions"/>
    <div xmlns="http://www.w3.org/1999/xhtml">
<div>
    <table class="grid dict">
        
        <tr>
            <th scope="row"><b>Id: </b></th>
            <td style="padding-left: 4px;">IMMZD2DTSeasonalinfluenzaSeasonalInfluenza</td>
        </tr>
        

        
        <tr>
            <th scope="row"><b>Url: </b></th>
            <td style="padding-left: 4px;"><a href="PlanDefinition-IMMZD2DTSeasonalinfluenzaSeasonalInfluenza.html">IMMZ.D2.DT.Seasonal influenza</a></td>
        </tr>
        

        
        <tr>
            <th scope="row"><b>Version: </b></th>
            <td style="padding-left: 4px;">1.0.0</td>
        </tr>
        

        

        
        <tr>
            <th scope="row"><b>Title: </b></th>
            <td style="padding-left: 4px;">IMMZ.D2.DT.Seasonal influenza</td>
        </tr>
        

        

        
        <tr>
            <th scope="row"><b>Status: </b></th>
            <td style="padding-left: 4px;">draft</td>
        </tr>
        

        

        
        <tr>
            <th scope="row"><b>Type: </b></th>
            <td style="padding-left: 4px;">
                
                    
                        
                        <p style="margin-bottom: 5px;">
                            <b>system: </b> <span><a href="http://terminology.hl7.org/7.1.0/CodeSystem-plan-definition-type.html">http://terminology.hl7.org/CodeSystem/plan-definition-type</a></span>
                        </p>
                        
                        
                        <p style="margin-bottom: 5px;">
                            <b>code: </b> <span>eca-rule</span>
                        </p>
                        
                        
                    
                
                
            </td>
        </tr>
        

        

        
        <tr>
            <th scope="row"><b>Date: </b></th>
            <td style="padding-left: 4px;">2026-03-31 13:54:17+0000</td>
        </tr>
        

        
        <tr>
            <th scope="row"><b>Publisher: </b></th>
            <td style="padding-left: 4px;">WHO</td>
        </tr>
        

        
        <tr>
            <th scope="row"><b>Description: </b></th>
            <td style="padding-left: 4px;"><div><p>IMMZ.D2.DT.Seasonal influenza
Inactivated trivalent and quadrivalent vaccines, 2-dose schedule</p>
</div></td>
        </tr>
        

        
        <tr>
            <th scope="row"><b>Knowledge Capability: </b></th>
            <td style="padding-left: 4px;">
                
                computable 
            </td>
        </tr>
        

        

        

        

        

        

        

        

        

        

        
        <tr>
            <th scope="row"><b>Related Artifacts: </b></th>
            <td style="padding-left: 4px;">
                
                
                <p><b>References</b></p>
                <ul>
                    
                    <li><div><p>WHO recommendations for routine immunization - summary tables (January 2025)</p>
</div><br/><a href="null"/></li>
                    
                </ul>
                
                
                
                
                
                
            </td>
        </tr>
        

        
        <tr>
            <th scope="row"><b>Libraries: </b></th>
            <td style="padding-left: 4px;">
                <table class="grid-dict">
                    
                    <tr>
                        <td><a href="Library-IMMZD2DTSeasonalinfluenzaSeasonalInfluenzaLogic.html">IMMZD2DTSeasonalinfluenzaSeasonalInfluenzaLogic</a></td>
                    </tr>
                    
                </table>
            </td>
        </tr>
        

        
        <tr>
            <th scope="row"><b>Actions: </b></th>
            <td style="padding-left: 4px;">
                <table class="grid-dict">
                    
                    <tr>
                        <td>
                            
                            <b> Determine if the client is due for Seasonal influenza.:</b> Determine if the client is due for Seasonal influenza vaccine according to the national immunization protocol.
Inactivated trivalent and quadrivalent vaccines, 2-dose schedule
                            
                            <br/>
                            
                            
                            <b>If:</b>
                            
                            <i>Applicability:</i>
                            
                            Client is due for seasonal influenza vaccination
                            
                            <i>(Client is due for seasonal influenza vaccination)</i>
                            <br/>
                            
                            
                            
                            
                            <b>Then:</b> <i>Definition:</i> <a href="ActivityDefinition-IMMZD2DTMR.html">IMMZD2DTMR</a><br/>
                            
                            <i>Dynamic Values:</i><br/>
                            
                            status: <i>('draft')</i>
                            <br/>
                            
                            intent: <i>('proposal')</i>
                            <br/>
                            
                            medication: <i>(Concept { codes: { Code { system: 'http://smart.who.int/immunizations/CodeSystem/IMMZ.Z', code: 'DE18', display: 'Seasonal influenza vaccines' } }, display: 'Seasonal influenza vaccines' })</i>
                            <br/>
                            
                            
                            
                            
                        </td>
                    </tr>
                    
                    <tr>
                        <td>
                            
                            <b> Determine if the client is due for Seasonal influenza.:</b> Determine if the client is due for Seasonal influenza vaccine according to the national immunization protocol.
Inactivated trivalent and quadrivalent vaccines, 2-dose schedule
                            
                            <br/>
                            
                            
                            <b>If:</b>
                            
                            <i>Applicability:</i>
                            
                            The primary series is complete. Client is due for seasonal influenza annual dose
                            
                            <i>(The primary series is complete. Client is due for seasonal influenza annual dose)</i>
                            <br/>
                            
                            
                            
                            
                            <b>Then:</b> <i>Definition:</i> <a href="ActivityDefinition-IMMZD2DTMR.html">IMMZD2DTMR</a><br/>
                            
                            <i>Dynamic Values:</i><br/>
                            
                            status: <i>('draft')</i>
                            <br/>
                            
                            intent: <i>('proposal')</i>
                            <br/>
                            
                            medication: <i>(Concept { codes: { Code { system: 'http://smart.who.int/immunizations/CodeSystem/IMMZ.Z', code: 'DE18', display: 'Seasonal influenza vaccines' } }, display: 'Seasonal influenza vaccines' })</i>
                            <br/>
                            
                            
                            
                            
                        </td>
                    </tr>
                    
                    <tr>
                        <td>
                            
                            <b> Check for Guidance for the patient regarding IMMZ.D2.DT.Seasonal influenza.:</b> Show Guidance for the patient regarding IMMZ.D2.DT.Seasonal influenza.
                            
                            <br/>
                            
                            
                            <b>If:</b>
                            
                            <i>Applicability:</i>
                            
                            Has Guidance
                            
                            <i>(Has Guidance)</i>
                            <br/>
                            
                            
                            
                            
                            <b>Then:</b> <i>Definition:</i> <a href="ActivityDefinition-IMMZD2DTCR.html">IMMZ.D2.DT.CR</a><br/>
                            
                            <i>Dynamic Values:</i><br/>
                            
                            status: <i>('active')</i>
                            <br/>
                            
                            payload.contentString: <i>(Guidance)</i>
                            <br/>
                            
                            category.coding: <i>(Code { system: 'http://terminology.hl7.org/CodeSystem/communication-category', code: 'alert' })</i>
                            <br/>
                            
                            priority: <i>(Code { system: 'http://hl7.org/fhir/request-priority', code: 'routine' })</i>
                            <br/>
                            
                            
                            
                            
                        </td>
                    </tr>
                    
                </table>
            </td>
        </tr>
        
    </table>
</div>
</div>
  </text>
  <contained>
    <Library>
      <id value="effective-data-requirements"/>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString value="IMMZEncounterElements"/>
        </extension>
        <extension url="name">
          <valueString value="Current Patient Age In Months"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="/** 
 * @dataElement Patient age in months
 */
define &quot;Current Patient Age In Months&quot;:
  AgeInMonthsAt(Today)"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="0"/>
        </extension>
      </extension>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString value="IMMZD2DTSeasonalinfluenzaEncounterElements"/>
        </extension>
        <extension url="name">
          <valueString value="Client's age is less than 6 months"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="/*
@input: Client's age is less than 6 months
@pseudocode: Today's date − &quot;Date of birth&quot; &lt; 6 months
@code: Client's age is less than 6 months-41
@decision: IMMZ.D2.DT.Seasonal influenza: Inactivated trivalent and quadrivalent vaccines, 2-dose schedule
*/
define &quot;Client's age is less than 6 months&quot;:
  Encounter.&quot;Current Patient Age In Months&quot; &lt; 6"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="1"/>
        </extension>
      </extension>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString
                       value="IMMZD2DTSeasonalinfluenzaSeasonalInfluenzaLogic"/>
        </extension>
        <extension url="name">
          <valueString
                       value="Client is not due for seasonal influenza vaccination Case 1"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="/*
@output: Client is not due for seasonal influenza vaccination Case 1
@pseudocode: &quot;Immunization recommendation status&quot; = &quot;Not due&quot;
*/
define &quot;Client is not due for seasonal influenza vaccination Case 1&quot;:
  Encounter.&quot;Client's age is less than 6 months&quot;"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="2"/>
        </extension>
      </extension>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString value="IMMZElements"/>
        </extension>
        <extension url="name">
          <valueString value="Doses Administered to Patient"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="/**
 * @dataElement All Doses Administered to Patient
 */
define &quot;Doses Administered to Patient&quot;:
  [Immunization] I
    where I.status = 'completed'
    and I.isSubpotent is not true"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="3"/>
        </extension>
      </extension>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString value="IMMZEncounterElements"/>
        </extension>
        <extension url="name">
          <valueString value="Doses Administered to Patient"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="/**
 * @dataElement All Doses Administered to Patient
 */
define &quot;Doses Administered to Patient&quot;:
  Elements.&quot;Doses Administered to Patient&quot; I
    where I.occurrence.toInterval() same day or before Today"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="4"/>
        </extension>
      </extension>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString value="IMMZD2DTSeasonalinfluenzaEncounterElements"/>
        </extension>
        <extension url="name">
          <valueString
                       value="Seasonal influenza Doses Administered to Patient"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="/*
@internal: Seasonal influenza containing Doses Administered to Patient
*/
define &quot;Seasonal influenza Doses Administered to Patient&quot;:
  Encounter.&quot;Doses Administered to Patient&quot; I
  where
    I.vaccineCode in Concepts.&quot;Seasonal influenza vaccines&quot;"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="5"/>
        </extension>
      </extension>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString value="IMMZD2DTSeasonalinfluenzaEncounterElements"/>
        </extension>
        <extension url="name">
          <valueString
                       value="Seasonal influenza Primary Series Doses Administered to Patient"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="/*
@internal: Seasonal influenza containing Doses Administered to Patient that are in the Primary series
*/
define &quot;Seasonal influenza Primary Series Doses Administered to Patient&quot;:
  &quot;Seasonal influenza Doses Administered to Patient&quot;.seriesPrimary()"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="6"/>
        </extension>
      </extension>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString value="IMMZD2DTSeasonalinfluenzaEncounterElements"/>
        </extension>
        <extension url="name">
          <valueString
                       value="Number of Seasonal influenza Primary Series Doses Administered"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="/*
@internal: Number of Seasonal influenza Primary Series doses
*/
define &quot;Number of Seasonal influenza Primary Series Doses Administered&quot;:
  Count(&quot;Seasonal influenza Primary Series Doses Administered to Patient&quot;)"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="7"/>
        </extension>
      </extension>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString value="IMMZD2DTSeasonalinfluenzaEncounterElements"/>
        </extension>
        <extension url="name">
          <valueString
                       value="One seasonal influenza primary series doses were administered"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="/*
@input: One seasonal influenza primary series doses were administered
@pseudocode: Count of vaccines administered (where &quot;Vaccine type&quot; = &quot;Seasonal influenza vaccines&quot; and &quot;Type of dose&quot; = &quot;Primary series&quot;) = 1
@code: One seasonal influenza primary series doses were administered-127
@decision: IMMZ.D2.DT.Seasonal influenza: Inactivated trivalent and quadrivalent vaccines, 2-dose schedule
*/
define &quot;One seasonal influenza primary series doses were administered&quot;:
  &quot;Number of Seasonal influenza Primary Series Doses Administered&quot; = 1"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="8"/>
        </extension>
      </extension>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString value="IMMZEncounterElements"/>
        </extension>
        <extension url="name">
          <valueString value="Current Patient Age In Years"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="/** 
 * @dataElement Patient age in years
 */
define &quot;Current Patient Age In Years&quot;:
  AgeInYearsAt(Today)"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="9"/>
        </extension>
      </extension>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString value="IMMZD2DTSeasonalinfluenzaEncounterElements"/>
        </extension>
        <extension url="name">
          <valueString value="Client's age is less than 9 years"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="/*
@input: Client's age is less than 9 years
@pseudocode: Today's date − &quot;Date of birth&quot; &lt; 9 years
@code: Client's age is less than 9 years-40
@decision: IMMZ.D2.DT.Seasonal influenza: Inactivated trivalent and quadrivalent vaccines, 2-dose schedule
*/
define &quot;Client's age is less than 9 years&quot;:
  Encounter.&quot;Current Patient Age In Years&quot; &lt; 9"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="10"/>
        </extension>
      </extension>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString value="IMMZD2DTSeasonalinfluenzaEncounterElements"/>
        </extension>
        <extension url="name">
          <valueString value="Date of Latest Seasonal influenza Dose"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="/*
@internal: Date of Latest Seasonal influenza Dose
*/
define &quot;Date of Latest Seasonal influenza Dose&quot;:
  date from start of &quot;Seasonal influenza Doses Administered to Patient&quot;.mostRecent().occurrence.toInterval()"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="11"/>
        </extension>
      </extension>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString value="IMMZD2DTSeasonalinfluenzaEncounterElements"/>
        </extension>
        <extension url="name">
          <valueString
                       value="The latest seasonal influenza dose was administered less than 4 weeks ago"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="/*
@input: The latest seasonal influenza dose was administered less than 4 weeks ago
@pseudocode: Today's date − &quot;Date and time of vaccination&quot; (where &quot;Vaccine type&quot; = &quot;Seasonal influenza vaccines&quot;) &lt; 4 weeks
@code: The latest seasonal influenza dose was administered less than 4 weeks ago-110
@decision: IMMZ.D2.DT.Seasonal influenza: Inactivated trivalent and quadrivalent vaccines, 2-dose schedule
*/
define &quot;The latest seasonal influenza dose was administered less than 4 weeks ago&quot;:
  &quot;Date of Latest Seasonal influenza Dose&quot; is not null
  and duration in weeks between &quot;Date of Latest Seasonal influenza Dose&quot; and Today &lt; 4"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="12"/>
        </extension>
      </extension>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString
                       value="IMMZD2DTSeasonalinfluenzaSeasonalInfluenzaLogic"/>
        </extension>
        <extension url="name">
          <valueString
                       value="Client is not due for seasonal influenza vaccination Case 2"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="/*
@output: Client is not due for seasonal influenza vaccination Case 2
@pseudocode: &quot;Immunization recommendation status&quot; = &quot;Not due&quot;
*/
define &quot;Client is not due for seasonal influenza vaccination Case 2&quot;:
  Encounter.&quot;One seasonal influenza primary series doses were administered&quot;
    and Encounter.&quot;Client's age is less than 9 years&quot;
    and Encounter.&quot;The latest seasonal influenza dose was administered less than 4 weeks ago&quot;"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="13"/>
        </extension>
      </extension>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString
                       value="IMMZD2DTSeasonalinfluenzaSeasonalInfluenzaLogic"/>
        </extension>
        <extension url="name">
          <valueString
                       value="Client is not due for seasonal influenza vaccination"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="/*
@output: Client is not due for seasonal influenza vaccination
@pseudocode: &quot;Immunization recommendation status&quot; = &quot;Not due&quot;
*/
define &quot;Client is not due for seasonal influenza vaccination&quot;:
  &quot;Client is not due for seasonal influenza vaccination Case 1&quot;
    or &quot;Client is not due for seasonal influenza vaccination Case 2&quot;"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="14"/>
        </extension>
      </extension>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString
                       value="IMMZD2DTSeasonalinfluenzaSeasonalInfluenzaLogic"/>
        </extension>
        <extension url="name">
          <valueString
                       value="Client is not due for seasonal influenza vaccination Guidance"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="/*
@output: Client is not due for seasonal influenza vaccination Guidance
@guidance = Should not vaccinate client with first seasonal influenza dose as client's age is less than 6 months. 
Check for any other vaccines due and inform the caregiver of when to come back for first dose.
@guidance = Should not vaccinate client with second seasonal influenza dose as latest seasonal influenza dose was administered less than 4 weeks ago. 
Check for any other vaccines due and inform the caregiver of when to come back for the second dose.
*/
define &quot;Client is not due for seasonal influenza vaccination Guidance&quot;:
  case
    when &quot;Client is not due for seasonal influenza vaccination Case 1&quot; then 'Should not vaccinate client with first seasonal influenza dose as client\'s age is less than 6 months. 
Check for any other vaccines due and inform the caregiver of when to come back for first dose.'
    when &quot;Client is not due for seasonal influenza vaccination Case 2&quot; then 'Should not vaccinate client with second seasonal influenza dose as latest seasonal influenza dose was administered less than 4 weeks ago. 
Check for any other vaccines due and inform the caregiver of when to come back for the second dose.'
    else ''
  end"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="15"/>
        </extension>
      </extension>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString value="IMMZD2DTSeasonalinfluenzaEncounterElements"/>
        </extension>
        <extension url="name">
          <valueString
                       value="No seasonal influenza primary series doses were administered"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="/*
@input: No seasonal influenza primary series doses were administered
@pseudocode: Count of vaccines administered (where &quot;Vaccine type&quot; = &quot;Seasonal influenza vaccines&quot; and &quot;Type of dose&quot; = &quot;Primary series&quot;) = 0
@code: No seasonal influenza primary series doses were administered-127
@decision: IMMZ.D2.DT.Seasonal influenza: Inactivated trivalent and quadrivalent vaccines, 2-dose schedule
*/
define &quot;No seasonal influenza primary series doses were administered&quot;:
  &quot;Number of Seasonal influenza Primary Series Doses Administered&quot; = 0"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="16"/>
        </extension>
      </extension>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString value="IMMZD2DTSeasonalinfluenzaEncounterElements"/>
        </extension>
        <extension url="name">
          <valueString
                       value="Client's age is more than or equal to 6 months"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="/*
@input: Client's age is more than or equal to 6 months
@pseudocode: Today's date − &quot;Date of birth&quot; ≥ 6 months
@code: Client's age is more than or equal to 6 months-41
@decision: IMMZ.D2.DT.Seasonal influenza: Inactivated trivalent and quadrivalent vaccines, 2-dose schedule
*/
define &quot;Client's age is more than or equal to 6 months&quot;:
  Encounter.&quot;Current Patient Age In Months&quot; &gt;= 6"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="17"/>
        </extension>
      </extension>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString
                       value="IMMZD2DTSeasonalinfluenzaSeasonalInfluenzaLogic"/>
        </extension>
        <extension url="name">
          <valueString
                       value="Client is due for seasonal influenza vaccination Case 1"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="/*
@output: Client is due for seasonal influenza vaccination Case 1
@pseudocode: &quot;Immunization recommendation status&quot; = &quot;Due&quot;
*/
define &quot;Client is due for seasonal influenza vaccination Case 1&quot;:
  Encounter.&quot;No seasonal influenza primary series doses were administered&quot;
    and Encounter.&quot;Client's age is more than or equal to 6 months&quot;"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="18"/>
        </extension>
      </extension>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString value="IMMZD2DTSeasonalinfluenzaEncounterElements"/>
        </extension>
        <extension url="name">
          <valueString
                       value="The latest seasonal influenza dose was administered more than 4 weeks ago"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="/*
@input: The latest seasonal influenza dose was administered more than 4 weeks ago
@pseudocode: Today's date − &quot;Date and time of vaccination&quot; (where &quot;Vaccine type&quot; = &quot;Seasonal influenza vaccines&quot;) ≥ 4 weeks
@code: The latest seasonal influenza dose was administered more than 4 weeks ago-110
@decision: IMMZ.D2.DT.Seasonal influenza: Inactivated trivalent and quadrivalent vaccines, 2-dose schedule
*/
define &quot;The latest seasonal influenza dose was administered more than 4 weeks ago&quot;:
  not &quot;The latest seasonal influenza dose was administered less than 4 weeks ago&quot;"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="19"/>
        </extension>
      </extension>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString
                       value="IMMZD2DTSeasonalinfluenzaSeasonalInfluenzaLogic"/>
        </extension>
        <extension url="name">
          <valueString
                       value="Client is due for seasonal influenza vaccination Case 2"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="/*
@output: Client is due for seasonal influenza vaccination Case 2
@pseudocode: &quot;Immunization recommendation status&quot; = &quot;Due&quot;
*/
define &quot;Client is due for seasonal influenza vaccination Case 2&quot;:
  Encounter.&quot;One seasonal influenza primary series doses were administered&quot;
    and Encounter.&quot;Client's age is less than 9 years&quot;
    and Encounter.&quot;The latest seasonal influenza dose was administered more than 4 weeks ago&quot;"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="20"/>
        </extension>
      </extension>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString
                       value="IMMZD2DTSeasonalinfluenzaSeasonalInfluenzaLogic"/>
        </extension>
        <extension url="name">
          <valueString
                       value="Client is due for seasonal influenza vaccination"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="/*
@output: Client is due for seasonal influenza vaccination
@pseudocode: &quot;Immunization recommendation status&quot; = &quot;Due&quot;
*/
define &quot;Client is due for seasonal influenza vaccination&quot;:
  &quot;Client is due for seasonal influenza vaccination Case 1&quot;
    or &quot;Client is due for seasonal influenza vaccination Case 2&quot;"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="21"/>
        </extension>
      </extension>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString
                       value="IMMZD2DTSeasonalinfluenzaSeasonalInfluenzaLogic"/>
        </extension>
        <extension url="name">
          <valueString
                       value="Client is due for seasonal influenza vaccination Guidance"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="/*
@output: Client is due for seasonal influenza vaccination Guidance
@guidance = Should vaccinate client with first seasonal influenza dose as no seasonal infuenza doses were administered and client is within appropriate age range. 
Check for contraindications.
@guidance = Should vaccinate client with second seasonal influenza dose as client is within appropriate age range and latest seasonal influenza dose was administerered more than 4 weeks ago.
Check for contraindications.
*/
define &quot;Client is due for seasonal influenza vaccination Guidance&quot;:
  case
    when &quot;Client is due for seasonal influenza vaccination Case 1&quot; then 'Should vaccinate client with first seasonal influenza dose as no seasonal infuenza doses were administered and client is within appropriate age range. 
Check for contraindications.'
    when &quot;Client is due for seasonal influenza vaccination Case 2&quot; then 'Should vaccinate client with second seasonal influenza dose as client is within appropriate age range and latest seasonal influenza dose was administerered more than 4 weeks ago.
Check for contraindications.'
    else ''
  end"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="22"/>
        </extension>
      </extension>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString value="IMMZD2DTSeasonalinfluenzaEncounterElements"/>
        </extension>
        <extension url="name">
          <valueString value="Client's age is more than or equal to 9 years"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="/*
@input: Client's age is more than or equal to 9 years
@pseudocode: Today's date − &quot;Date of birth&quot; ≥ 9 years
@code: Client's age is more than or equal to 9 years-40
@decision: IMMZ.D2.DT.Seasonal influenza: Inactivated trivalent and quadrivalent vaccines, 2-dose schedule
*/
define &quot;Client's age is more than or equal to 9 years&quot;:
  Encounter.&quot;Current Patient Age In Years&quot; &gt;= 9"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="23"/>
        </extension>
      </extension>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString value="IMMZD2DTSeasonalinfluenzaEncounterElements"/>
        </extension>
        <extension url="name">
          <valueString
                       value="The latest seasonal influenza dose was administered less than 1 year ago"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="/*
@input: The latest seasonal influenza dose was administered less than 1 year ago
@pseudocode: Today's date − &quot;Date and time of vaccination&quot; (where &quot;Vaccine type&quot; = &quot;Seasonal influenza vaccines&quot;) &lt; 1 year
@code: The latest seasonal influenza dose was administered less than 1 year ago-109
@decision: IMMZ.D2.DT.Seasonal influenza: Inactivated trivalent and quadrivalent vaccines, 2-dose schedule
*/
define &quot;The latest seasonal influenza dose was administered less than 1 year ago&quot;:
  &quot;Date of Latest Seasonal influenza Dose&quot; is not null
  and duration in years between &quot;Date of Latest Seasonal influenza Dose&quot; and Today &lt; 1"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="24"/>
        </extension>
      </extension>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString
                       value="IMMZD2DTSeasonalinfluenzaSeasonalInfluenzaLogic"/>
        </extension>
        <extension url="name">
          <valueString
                       value="The primary series is complete. Client is not due for seasonal influenza annual dose Case 1"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="/*
@output: The primary series is complete. Client is not due for seasonal influenza annual dose Case 1
@pseudocode: &quot;Immunization recommendation status&quot; = &quot;Not due&quot;
&quot;Completed the primary vaccination series&quot; (where &quot;Vaccine type&quot; = &quot;Seasonal influenza vaccines&quot;) = TRUE
*/
define &quot;The primary series is complete. Client is not due for seasonal influenza annual dose Case 1&quot;:
  Encounter.&quot;One seasonal influenza primary series doses were administered&quot;
    and Encounter.&quot;Client's age is more than or equal to 9 years&quot;
    and Encounter.&quot;The latest seasonal influenza dose was administered less than 1 year ago&quot;"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="25"/>
        </extension>
      </extension>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString value="IMMZD2DTSeasonalinfluenzaEncounterElements"/>
        </extension>
        <extension url="name">
          <valueString
                       value="Two seasonal influenza primary series doses were administered"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="/*
@input: Two seasonal influenza primary series doses were administered
@pseudocode: Count of vaccines administered (where &quot;Vaccine type&quot; = &quot;Seasonal influenza vaccines&quot; and &quot;Type of dose&quot; = &quot;Primary series&quot;) = 2
@code: Two seasonal influenza primary series doses were administered-127
@decision: IMMZ.D2.DT.Seasonal influenza: Inactivated trivalent and quadrivalent vaccines, 2-dose schedule
*/
define &quot;Two seasonal influenza primary series doses were administered&quot;:
  &quot;Number of Seasonal influenza Primary Series Doses Administered&quot; = 2"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="26"/>
        </extension>
      </extension>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString
                       value="IMMZD2DTSeasonalinfluenzaSeasonalInfluenzaLogic"/>
        </extension>
        <extension url="name">
          <valueString
                       value="The primary series is complete. Client is not due for seasonal influenza annual dose Case 2"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="/*
@output: The primary series is complete. Client is not due for seasonal influenza annual dose Case 2
@pseudocode: &quot;Immunization recommendation status&quot; = &quot;Not due&quot;
&quot;Completed the primary vaccination series&quot; (where &quot;Vaccine type&quot; = &quot;Seasonal influenza vaccines&quot;) = TRUE
*/
define &quot;The primary series is complete. Client is not due for seasonal influenza annual dose Case 2&quot;:
  Encounter.&quot;Two seasonal influenza primary series doses were administered&quot;
    and Encounter.&quot;The latest seasonal influenza dose was administered less than 1 year ago&quot;"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="27"/>
        </extension>
      </extension>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString
                       value="IMMZD2DTSeasonalinfluenzaSeasonalInfluenzaLogic"/>
        </extension>
        <extension url="name">
          <valueString
                       value="The primary series is complete. Client is not due for seasonal influenza annual dose"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="/*
@output: The primary series is complete. Client is not due for seasonal influenza annual dose
@pseudocode: &quot;Immunization recommendation status&quot; = &quot;Not due&quot;
&quot;Completed the primary vaccination series&quot; (where &quot;Vaccine type&quot; = &quot;Seasonal influenza vaccines&quot;) = TRUE
*/
define &quot;The primary series is complete. Client is not due for seasonal influenza annual dose&quot;:
  &quot;The primary series is complete. Client is not due for seasonal influenza annual dose Case 1&quot;
    or &quot;The primary series is complete. Client is not due for seasonal influenza annual dose Case 2&quot;"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="28"/>
        </extension>
      </extension>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString
                       value="IMMZD2DTSeasonalinfluenzaSeasonalInfluenzaLogic"/>
        </extension>
        <extension url="name">
          <valueString
                       value="The primary series is complete. Client is not due for seasonal influenza annual dose Guidance"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="/*
@output: The primary series is complete. Client is not due for seasonal influenza annual dose Guidance
@guidance = Should not vaccinate client with annual dose as the latest seasonal influenza dose was administered less than 1 year ago. 
Check for any other vaccines due and inform the caregiver of when to come back for the next dose.
@guidance = Should not vaccinate client with annual dose as latest seasonal influenza dose was administered less than 1 year ago. 
Check for any other vaccines due and inform the caregiver of when to come back for the next dose.
*/
define &quot;The primary series is complete. Client is not due for seasonal influenza annual dose Guidance&quot;:
  case
    when &quot;The primary series is complete. Client is not due for seasonal influenza annual dose Case 1&quot; then 'Should not vaccinate client with annual dose as the latest seasonal influenza dose was administered less than 1 year ago. 
Check for any other vaccines due and inform the caregiver of when to come back for the next dose.'
    when &quot;The primary series is complete. Client is not due for seasonal influenza annual dose Case 2&quot; then 'Should not vaccinate client with annual dose as latest seasonal influenza dose was administered less than 1 year ago. 
Check for any other vaccines due and inform the caregiver of when to come back for the next dose.'
    else ''
  end"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="29"/>
        </extension>
      </extension>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString value="IMMZD2DTSeasonalinfluenzaEncounterElements"/>
        </extension>
        <extension url="name">
          <valueString
                       value="The latest seasonal influenza dose was administered more than 1 year ago"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="/*
@input: The latest seasonal influenza dose was administered more than 1 year ago
@pseudocode: Today's date − &quot;Date and time of vaccination&quot; (where &quot;Vaccine type&quot; = &quot;Seasonal influenza vaccines&quot;) ≥ 1 year
@code: The latest seasonal influenza dose was administered more than 1 year ago-109
@decision: IMMZ.D2.DT.Seasonal influenza: Inactivated trivalent and quadrivalent vaccines, 2-dose schedule
*/
define &quot;The latest seasonal influenza dose was administered more than 1 year ago&quot;:
  not &quot;The latest seasonal influenza dose was administered less than 1 year ago&quot;"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="30"/>
        </extension>
      </extension>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString
                       value="IMMZD2DTSeasonalinfluenzaSeasonalInfluenzaLogic"/>
        </extension>
        <extension url="name">
          <valueString
                       value="The primary series is complete. Client is due for seasonal influenza annual dose Case 1"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="/*
@output: The primary series is complete. Client is due for seasonal influenza annual dose Case 1
@pseudocode: &quot;Immunization recommendation status&quot; = &quot;Due&quot;
&quot;Completed the primary vaccination series&quot; (where &quot;Vaccine type&quot; = &quot;Seasonal influenza vaccines&quot;) = TRUE
*/
define &quot;The primary series is complete. Client is due for seasonal influenza annual dose Case 1&quot;:
  Encounter.&quot;One seasonal influenza primary series doses were administered&quot;
    and Encounter.&quot;Client's age is more than or equal to 9 years&quot;
    and Encounter.&quot;The latest seasonal influenza dose was administered more than 1 year ago&quot;"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="31"/>
        </extension>
      </extension>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString
                       value="IMMZD2DTSeasonalinfluenzaSeasonalInfluenzaLogic"/>
        </extension>
        <extension url="name">
          <valueString
                       value="The primary series is complete. Client is due for seasonal influenza annual dose Case 2"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="/*
@output: The primary series is complete. Client is due for seasonal influenza annual dose Case 2
@pseudocode: &quot;Immunization recommendation status&quot; = &quot;Due&quot;
&quot;Completed the primary vaccination series&quot; (where &quot;Vaccine type&quot; = &quot;Seasonal influenza vaccines&quot;) = TRUE
*/
define &quot;The primary series is complete. Client is due for seasonal influenza annual dose Case 2&quot;:
  Encounter.&quot;Two seasonal influenza primary series doses were administered&quot;
    and Encounter.&quot;The latest seasonal influenza dose was administered more than 1 year ago&quot;"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="32"/>
        </extension>
      </extension>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString
                       value="IMMZD2DTSeasonalinfluenzaSeasonalInfluenzaLogic"/>
        </extension>
        <extension url="name">
          <valueString
                       value="The primary series is complete. Client is due for seasonal influenza annual dose"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="/*
@output: The primary series is complete. Client is due for seasonal influenza annual dose
@pseudocode: &quot;Immunization recommendation status&quot; = &quot;Due&quot;
&quot;Completed the primary vaccination series&quot; (where &quot;Vaccine type&quot; = &quot;Seasonal influenza vaccines&quot;) = TRUE
*/
define &quot;The primary series is complete. Client is due for seasonal influenza annual dose&quot;:
  &quot;The primary series is complete. Client is due for seasonal influenza annual dose Case 1&quot;
    or &quot;The primary series is complete. Client is due for seasonal influenza annual dose Case 2&quot;"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="33"/>
        </extension>
      </extension>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString
                       value="IMMZD2DTSeasonalinfluenzaSeasonalInfluenzaLogic"/>
        </extension>
        <extension url="name">
          <valueString
                       value="The primary series is complete. Client is due for seasonal influenza annual dose Guidance"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="/*
@output: The primary series is complete. Client is due for seasonal influenza annual dose Guidance
@guidance = Should vaccinate client with annual dose as the latest seasonal influenza dose was administered more than 1 year ago. 
Check for contraindications.
@guidance = Should vaccinate client with annual dose as latest seasonal influenza dose was administered more than 1 year ago. 
Check for contraindications.
*/
define &quot;The primary series is complete. Client is due for seasonal influenza annual dose Guidance&quot;:
  case
    when &quot;The primary series is complete. Client is due for seasonal influenza annual dose Case 1&quot; then 'Should vaccinate client with annual dose as the latest seasonal influenza dose was administered more than 1 year ago. 
Check for contraindications.'
    when &quot;The primary series is complete. Client is due for seasonal influenza annual dose Case 2&quot; then 'Should vaccinate client with annual dose as latest seasonal influenza dose was administered more than 1 year ago. 
Check for contraindications.'
    else ''
  end"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="34"/>
        </extension>
      </extension>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString
                       value="IMMZD2DTSeasonalinfluenzaSeasonalInfluenzaLogic"/>
        </extension>
        <extension url="name">
          <valueString value="Guidance"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="/*
@dynamicValue: Guidance
*/
define &quot;Guidance&quot;:
  case 
    when &quot;Client is not due for seasonal influenza vaccination&quot; then &quot;Client is not due for seasonal influenza vaccination Guidance&quot;
    when &quot;Client is due for seasonal influenza vaccination&quot; then &quot;Client is due for seasonal influenza vaccination Guidance&quot;
    when &quot;The primary series is complete. Client is not due for seasonal influenza annual dose&quot; then &quot;The primary series is complete. Client is not due for seasonal influenza annual dose Guidance&quot;
    when &quot;The primary series is complete. Client is due for seasonal influenza annual dose&quot; then &quot;The primary series is complete. Client is due for seasonal influenza annual dose Guidance&quot; 
    else ''
  end"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="35"/>
        </extension>
      </extension>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString
                       value="IMMZD2DTSeasonalinfluenzaSeasonalInfluenzaLogic"/>
        </extension>
        <extension url="name">
          <valueString value="Has Guidance"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="define &quot;Has Guidance&quot;:
  &quot;Guidance&quot; is not null and &quot;Guidance&quot; != ''"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="36"/>
        </extension>
      </extension>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString value="IMMZCommon"/>
        </extension>
        <extension url="name">
          <valueString value="seriesPrimary"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="/**
 * @description: Gets the doses from the primary series
 */
define fluent function seriesPrimary(immunizations List&lt;Immunization&gt;):
  immunizations I where
    exists( I.protocolApplied pa where pa.series = 'Primary series' )"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="37"/>
        </extension>
      </extension>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString value="FHIRHelpers"/>
        </extension>
        <extension url="name">
          <valueString value="ToString"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="define function ToString(value string): value.value"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="38"/>
        </extension>
      </extension>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString value="FHIRHelpers"/>
        </extension>
        <extension url="name">
          <valueString value="ToString"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="define function ToString(value ImmunizationStatus): value.value"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="39"/>
        </extension>
      </extension>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString value="FHIRHelpers"/>
        </extension>
        <extension url="name">
          <valueString value="ToBoolean"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="define function ToBoolean(value boolean): value.value"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="40"/>
        </extension>
      </extension>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString value="WHOCommon"/>
        </extension>
        <extension url="name">
          <valueString value="toInterval"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="/*
From FHIRCommon 4.1.0:
*/

/*
@description: Normalizes a value that is a choice of timing-valued types to an equivalent interval
@comment: Normalizes a choice type of FHIR.dateTime, FHIR.Period, FHIR.Timing, FHIR.instance, FHIR.string, FHIR.Age, or FHIR.Range types
to an equivalent interval. This selection of choice types is a superset of the majority of choice types that are used as possible
representations for timing-valued elements in FHIR, allowing this function to be used across any resource.

The input can be provided as a dateTime, Period, Timing, instant, string, Age, or Range.
The intent of this function is to provide a clear and concise mechanism to treat single
elements that have multiple possible representations as intervals so that logic doesn't have to account
for the variability. More complex calculations (such as medication request period or dispense period
calculation) need specific guidance and consideration. That guidance may make use of this function, but
the focus of this function is on single element calculations where the semantics are unambiguous.
If the input is a dateTime, the result a DateTime Interval beginning and ending on that dateTime.
If the input is a Period, the result is a DateTime Interval.
If the input is a Timing, an error is raised indicating a single interval cannot be computed from a Timing.
If the input is an instant, the result is a DateTime Interval beginning and ending on that instant.
If the input is a string, an error is raised indicating a single interval cannot be computed from a string.
If the input is an Age, the result is a DateTime Interval beginning when the patient was the given Age,
and ending immediately prior to when the patient was the given Age plus one year.
If the input is a Range, the result is a DateTime Interval beginning when the patient was the Age given
by the low end of the Range, and ending immediately prior to when the patient was the Age given by the
high end of the Range plus one year.

NOTE: Due to the
complexity of determining a single interval from a Timing or String type, this function will throw a run-time exception if it is used
with a Timing or String.
*/
define fluent function toInterval(choice Choice&lt;FHIR.dateTime, FHIR.Period, FHIR.Timing, FHIR.instant, FHIR.string, FHIR.Age, FHIR.Range&gt;):
  case
    when choice is FHIR.dateTime then
      Interval[FHIRHelpers.ToDateTime(choice as FHIR.dateTime), FHIRHelpers.ToDateTime(choice as FHIR.dateTime)]
    when choice is FHIR.Period then
      FHIRHelpers.ToInterval(choice as FHIR.Period)
    when choice is FHIR.instant then
      Interval[FHIRHelpers.ToDateTime(choice as FHIR.instant), FHIRHelpers.ToDateTime(choice as FHIR.instant)]
    when choice is FHIR.Age then
      Interval[FHIRHelpers.ToDate(Patient.birthDate) + FHIRHelpers.ToQuantity(choice as FHIR.Age),
        FHIRHelpers.ToDate(Patient.birthDate) + FHIRHelpers.ToQuantity(choice as FHIR.Age) + 1 year)
    when choice is FHIR.Range then
      Interval[FHIRHelpers.ToDate(Patient.birthDate) + FHIRHelpers.ToQuantity((choice as FHIR.Range).low),
        FHIRHelpers.ToDate(Patient.birthDate) + FHIRHelpers.ToQuantity((choice as FHIR.Range).high) + 1 year)
    when choice is FHIR.Timing then
      Message(null as Interval&lt;DateTime&gt;, true, 'NOT_IMPLEMENTED', 'Error', 'Calculation of an interval from a Timing value is not supported')
    when choice is FHIR.string then
      Message(null as Interval&lt;DateTime&gt;, true, 'NOT_IMPLEMENTED', 'Error', 'Calculation of an interval from a String value is not supported')
    else
      null as Interval&lt;DateTime&gt;
  end"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="41"/>
        </extension>
      </extension>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString value="FHIRHelpers"/>
        </extension>
        <extension url="name">
          <valueString value="ToDateTime"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="define function ToDateTime(value dateTime): value.value"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="42"/>
        </extension>
      </extension>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString value="FHIRHelpers"/>
        </extension>
        <extension url="name">
          <valueString value="ToInterval"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="define function ToInterval(period FHIR.Period):
    if period is null then
        null
    else
        if period.&quot;start&quot; is null then
            Interval(period.&quot;start&quot;.value, period.&quot;end&quot;.value]
        else
            Interval[period.&quot;start&quot;.value, period.&quot;end&quot;.value]"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="43"/>
        </extension>
      </extension>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString value="FHIRHelpers"/>
        </extension>
        <extension url="name">
          <valueString value="ToDateTime"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="define function ToDateTime(value instant): value.value"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="44"/>
        </extension>
      </extension>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString value="FHIRHelpers"/>
        </extension>
        <extension url="name">
          <valueString value="ToDate"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="define function ToDate(value date): value.value"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="45"/>
        </extension>
      </extension>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString value="FHIRHelpers"/>
        </extension>
        <extension url="name">
          <valueString value="ToQuantity"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="define function ToQuantity(quantity FHIR.Quantity):
    case
        when quantity is null then null
        when quantity.value is null then null
        when quantity.comparator is not null then
            Message(null, true, 'FHIRHelpers.ToQuantity.ComparatorQuantityNotSupported', 'Error', 'FHIR Quantity value has a comparator and cannot be converted to a System.Quantity value.')
        when quantity.system is null or quantity.system.value = 'http://unitsofmeasure.org'
              or quantity.system.value = 'http://hl7.org/fhirpath/CodeSystem/calendar-units' then
            System.Quantity { value: quantity.value.value, unit: ToCalendarUnit(Coalesce(quantity.code.value, quantity.unit.value, '1')) }
        else
            Message(null, true, 'FHIRHelpers.ToQuantity.InvalidFHIRQuantity', 'Error', 'Invalid FHIR Quantity code: ' &amp; quantity.unit.value &amp; ' (' &amp; quantity.system.value &amp; '|' &amp; quantity.code.value &amp; ')')
    end"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="46"/>
        </extension>
      </extension>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString value="FHIRHelpers"/>
        </extension>
        <extension url="name">
          <valueString value="ToCalendarUnit"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="define function ToCalendarUnit(unit System.String):
    case unit
        when 'ms' then 'millisecond'
        when 's' then 'second'
        when 'min' then 'minute'
        when 'h' then 'hour'
        when 'd' then 'day'
        when 'wk' then 'week'
        when 'mo' then 'month'
        when 'a' then 'year'
        else unit
    end"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="47"/>
        </extension>
      </extension>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString value="FHIRHelpers"/>
        </extension>
        <extension url="name">
          <valueString value="ToConcept"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="define function ToConcept(concept FHIR.CodeableConcept):
    if concept is null then
        null
    else
        System.Concept {
            codes: concept.coding C return ToCode(C),
            display: concept.text.value
        }"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="48"/>
        </extension>
      </extension>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString value="FHIRHelpers"/>
        </extension>
        <extension url="name">
          <valueString value="ToCode"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="define function ToCode(coding FHIR.Coding):
    if coding is null then
        null
    else
        System.Code {
          code: coding.code.value,
          system: coding.system.value,
          version: coding.version.value,
          display: coding.display.value
        }"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="49"/>
        </extension>
      </extension>
      <extension
                 url="http://hl7.org/fhir/StructureDefinition/cqf-logicDefinition">
        <extension url="libraryName">
          <valueString value="WHOCommon"/>
        </extension>
        <extension url="name">
          <valueString value="mostRecent"/>
        </extension>
        <extension url="statement">
          <valueString
                       value="define fluent function mostRecent(immunizations List&lt;Immunization&gt;):
  Last(
    immunizations I
      sort by start of occurrence.toInterval()
  )"/>
        </extension>
        <extension url="displaySequence">
          <valueInteger value="50"/>
        </extension>
      </extension>
      <name value="EffectiveDataRequirements"/>
      <status value="active"/>
      <type>
        <coding>
          <system value="http://terminology.hl7.org/CodeSystem/library-type"/>
          <code value="module-definition"/>
        </coding>
      </type>
      <relatedArtifact>
        <type value="depends-on"/>
        <display value="FHIR model information"/>
        <resource
                  value="http://fhir.org/guides/cqf/common/Library/FHIR-ModelInfo|4.0.1"/>
      </relatedArtifact>
      <relatedArtifact>
        <type value="depends-on"/>
        <display value="Library Encounter"/>
        <resource
                  value="http://smart.who.int/immunizations/Library/IMMZD2DTSeasonalinfluenzaEncounterElements"/>
      </relatedArtifact>
      <relatedArtifact>
        <type value="depends-on"/>
        <display value="Library Encounter"/>
        <resource
                  value="http://smart.who.int/immunizations/Library/IMMZEncounterElements"/>
      </relatedArtifact>
      <relatedArtifact>
        <type value="depends-on"/>
        <display value="Library Common"/>
        <resource
                  value="http://smart.who.int/immunizations/Library/IMMZCommon"/>
      </relatedArtifact>
      <relatedArtifact>
        <type value="depends-on"/>
        <display value="Library FHIRHelpers"/>
        <resource
                  value="http://fhir.org/guides/cqf/common/Library/FHIRHelpers|4.0.1"/>
      </relatedArtifact>
      <relatedArtifact>
        <type value="depends-on"/>
        <display value="Library Elements"/>
        <resource
                  value="http://smart.who.int/immunizations/Library/IMMZElements"/>
      </relatedArtifact>
      <relatedArtifact>
        <type value="depends-on"/>
        <display value="Library WC"/>
        <resource
                  value="http://smart.who.int/immunizations/Library/WHOCommon"/>
      </relatedArtifact>
      <relatedArtifact>
        <type value="depends-on"/>
        <display value="Library Concepts"/>
        <resource
                  value="http://smart.who.int/immunizations/Library/IMMZConcepts"/>
      </relatedArtifact>
      <relatedArtifact>
        <type value="depends-on"/>
        <display value="Value set Seasonal influenza vaccines"/>
        <resource
                  value="http://smart.who.int/immunizations/ValueSet/IMMZ.Z.DE18"/>
      </relatedArtifact>
      <parameter>
        <name value="Today"/>
        <use value="in"/>
        <min value="0"/>
        <max value="1"/>
        <type value="date"/>
      </parameter>
      <parameter>
        <name value="Guidance"/>
        <use value="out"/>
        <min value="0"/>
        <max value="1"/>
        <type value="string"/>
      </parameter>
      <parameter>
        <name value="Client is due for seasonal influenza vaccination"/>
        <use value="out"/>
        <min value="0"/>
        <max value="1"/>
        <type value="boolean"/>
      </parameter>
      <parameter>
        <name value="Has Guidance"/>
        <use value="out"/>
        <min value="0"/>
        <max value="1"/>
        <type value="boolean"/>
      </parameter>
      <parameter>
        <name
              value="The primary series is complete. Client is due for seasonal influenza annual dose"/>
        <use value="out"/>
        <min value="0"/>
        <max value="1"/>
        <type value="boolean"/>
      </parameter>
      <dataRequirement>
        <type value="Patient"/>
        <profile value="http://hl7.org/fhir/StructureDefinition/Patient"/>
        <mustSupport value="birthDate"/>
      </dataRequirement>
      <dataRequirement>
        <type value="Immunization"/>
        <profile
                 value="http://hl7.org/fhir/StructureDefinition/Immunization"/>
        <mustSupport value="status"/>
        <mustSupport value="isSubpotent"/>
        <mustSupport value="protocolApplied"/>
        <mustSupport value="occurrence"/>
        <codeFilter>
          <path value="status"/>
          <code>
            <code value="completed"/>
          </code>
        </codeFilter>
      </dataRequirement>
      <dataRequirement>
        <type value="Immunization"/>
        <profile
                 value="http://hl7.org/fhir/StructureDefinition/Immunization"/>
        <mustSupport value="occurrence"/>
        <mustSupport value="protocolApplied"/>
      </dataRequirement>
      <dataRequirement>
        <type value="Immunization"/>
        <profile
                 value="http://hl7.org/fhir/StructureDefinition/Immunization"/>
        <mustSupport value="status"/>
        <mustSupport value="isSubpotent"/>
        <mustSupport value="occurrence"/>
        <mustSupport value="vaccineCode"/>
        <mustSupport value="protocolApplied"/>
        <codeFilter>
          <path value="status"/>
          <code>
            <code value="completed"/>
          </code>
        </codeFilter>
        <codeFilter>
          <path value="vaccineCode"/>
          <valueSet
                    value="http://smart.who.int/immunizations/ValueSet/IMMZ.Z.DE18"/>
        </codeFilter>
      </dataRequirement>
    </Library>
  </contained>
  <extension
             url="http://hl7.org/fhir/uv/cpg/StructureDefinition/cpg-knowledgeCapability">
    <valueCode value="computable"/>
  </extension>
  <extension
             url="http://hl7.org/fhir/uv/crmi/StructureDefinition/crmi-effectiveDataRequirements">
    <valueCanonical value="#effective-data-requirements"/>
  </extension>
  <url
       value="http://smart.who.int/immunizations/PlanDefinition/IMMZD2DTSeasonalinfluenzaSeasonalInfluenza"/>
  <version value="1.0.0"/>
  <name value="IMMZD2DTSeasonalinfluenzaSeasonalInfluenza"/>
  <title value="IMMZ.D2.DT.Seasonal influenza"/>
  <type>
    <coding>
      <system
              value="http://terminology.hl7.org/CodeSystem/plan-definition-type"/>
      <code value="eca-rule"/>
    </coding>
  </type>
  <status value="draft"/>
  <experimental value="false"/>
  <date value="2026-03-31T13:54:17+00:00"/>
  <publisher value="WHO"/>
  <contact>
    <name value="WHO"/>
    <telecom>
      <system value="url"/>
      <value value="http://who.int"/>
    </telecom>
  </contact>
  <description
               value="IMMZ.D2.DT.Seasonal influenza
Inactivated trivalent and quadrivalent vaccines, 2-dose schedule"/>
  <relatedArtifact>
    <type value="citation"/>
    <citation
              value="WHO recommendations for routine immunization - summary tables (January 2025)"/>
  </relatedArtifact>
  <library
           value="http://smart.who.int/immunizations/Library/IMMZD2DTSeasonalinfluenzaSeasonalInfluenzaLogic"/>
  <action>
    <extension
               url="http://hl7.org/fhir/uv/cpg/StructureDefinition/cpg-rationale">
      <valueMarkdown
                     value="Influenza vaccines are safe and effective in children from 6 months of age. Children aged under 6 months can be protected through maternal 
immunization during pregnancy. 
Children aged 6 months to 8 years should receive 2 doses at least 4 weeks apart. A single dose is appropriate for those ≥ 9 years of age and healthy adults.
Children aged 6 months to 8 years should receive 2 doses at least 4 weeks apart."/>
    </extension>
    <title value="Determine if the client is due for Seasonal influenza."/>
    <description
                 value="Determine if the client is due for Seasonal influenza vaccine according to the national immunization protocol.
Inactivated trivalent and quadrivalent vaccines, 2-dose schedule"/>
    <condition>
      <kind value="applicability"/>
      <expression>
        <description
                     value="Client is due for seasonal influenza vaccination"/>
        <language value="text/cql-identifier"/>
        <expression value="Client is due for seasonal influenza vaccination"/>
      </expression>
    </condition>
    <definitionCanonical
                         value="http://smart.who.int/immunizations/ActivityDefinition/IMMZD2DTMR"/>
    <dynamicValue>
      <path value="status"/>
      <expression>
        <language value="text/cql-expression"/>
        <expression value="'draft'"/>
      </expression>
    </dynamicValue>
    <dynamicValue>
      <path value="intent"/>
      <expression>
        <language value="text/cql-expression"/>
        <expression value="'proposal'"/>
      </expression>
    </dynamicValue>
    <dynamicValue>
      <path value="medication"/>
      <expression>
        <language value="text/cql-expression"/>
        <expression
                    value="Concept { codes: { Code { system: 'http://smart.who.int/immunizations/CodeSystem/IMMZ.Z', code: 'DE18', display: 'Seasonal influenza vaccines' } }, display: 'Seasonal influenza vaccines' }"/>
      </expression>
    </dynamicValue>
  </action>
  <action>
    <extension
               url="http://hl7.org/fhir/uv/cpg/StructureDefinition/cpg-rationale">
      <valueMarkdown
                     value="A single dose is appropriate for children aged ≥ 9 years and healthy adults. Those who have previously 
been vaccinated at least once should subsequently receive an annual dose, as should children and adolescents aged
 9 years or over and healthy adults."/>
    </extension>
    <title value="Determine if the client is due for Seasonal influenza."/>
    <description
                 value="Determine if the client is due for Seasonal influenza vaccine according to the national immunization protocol.
Inactivated trivalent and quadrivalent vaccines, 2-dose schedule"/>
    <condition>
      <kind value="applicability"/>
      <expression>
        <description
                     value="The primary series is complete. Client is due for seasonal influenza annual dose"/>
        <language value="text/cql-identifier"/>
        <expression
                    value="The primary series is complete. Client is due for seasonal influenza annual dose"/>
      </expression>
    </condition>
    <definitionCanonical
                         value="http://smart.who.int/immunizations/ActivityDefinition/IMMZD2DTMR"/>
    <dynamicValue>
      <path value="status"/>
      <expression>
        <language value="text/cql-expression"/>
        <expression value="'draft'"/>
      </expression>
    </dynamicValue>
    <dynamicValue>
      <path value="intent"/>
      <expression>
        <language value="text/cql-expression"/>
        <expression value="'proposal'"/>
      </expression>
    </dynamicValue>
    <dynamicValue>
      <path value="medication"/>
      <expression>
        <language value="text/cql-expression"/>
        <expression
                    value="Concept { codes: { Code { system: 'http://smart.who.int/immunizations/CodeSystem/IMMZ.Z', code: 'DE18', display: 'Seasonal influenza vaccines' } }, display: 'Seasonal influenza vaccines' }"/>
      </expression>
    </dynamicValue>
  </action>
  <action>
    <title
           value="Check for Guidance for the patient regarding IMMZ.D2.DT.Seasonal influenza."/>
    <description
                 value="Show Guidance for the patient regarding IMMZ.D2.DT.Seasonal influenza."/>
    <condition>
      <kind value="applicability"/>
      <expression>
        <description value="Has Guidance"/>
        <language value="text/cql-identifier"/>
        <expression value="Has Guidance"/>
      </expression>
    </condition>
    <definitionCanonical
                         value="http://smart.who.int/immunizations/ActivityDefinition/IMMZD2DTCR"/>
    <dynamicValue>
      <path value="status"/>
      <expression>
        <language value="text/cql-expression"/>
        <expression value="'active'"/>
      </expression>
    </dynamicValue>
    <dynamicValue>
      <path value="payload.contentString"/>
      <expression>
        <language value="text/cql-identifier"/>
        <expression value="Guidance"/>
      </expression>
    </dynamicValue>
    <dynamicValue>
      <path value="category.coding"/>
      <expression>
        <description value="Category of communication"/>
        <language value="text/cql-expression"/>
        <expression
                    value="Code { system: 'http://terminology.hl7.org/CodeSystem/communication-category', code: 'alert' }"/>
      </expression>
    </dynamicValue>
    <dynamicValue>
      <path value="priority"/>
      <expression>
        <description value="Alert priority"/>
        <language value="text/cql-expression"/>
        <expression
                    value="Code { system: 'http://hl7.org/fhir/request-priority', code: 'routine' }"/>
      </expression>
    </dynamicValue>
  </action>
</PlanDefinition>