The product entry describes an immunization used in a <substanceAdministration> act.
                                    It adopts the constraints of the ASTM/HL7 Continuity of Care Document. 
                                 
                                 
                                 In a CDA document, the name and strength of the immunization administered are specified
                                    in the elements under the <manufacturedMaterial> element. The templateId elements
                                    are required and identify this as a product entry. 
                                 
                                 
                                 
                                 
                                 The <code> element of the <manufacturedMaterial> describes the vaccine. The values
                                    for the code attribute come from the epSOSVaccine value set (OID 1.3.6.1.4.1.12559.11.10.1.3.1.42.28).
                                    The code system is SNOMED CT (codeSystem OID 2.16.840.1.113883.6.96).The <originalText>
                                    shall contain a <reference> whose URI value points to the generic name and strength
                                    of the medication, or just the generic name alone if strength is not relevant.Note: When the text is supplied from the narrative, the implication is that if you
                                    supply the components of a combination vaccine in an entry, you must also display
                                    these in the narrative text, otherwise you would not be able to break the combination
                                    vaccine down into its component parts. This is entirely consistent with the CDA Release
                                    2.0 requirements that the narrative supply the necessary and relevant human readable
                                    information content. 
                                 
                                 
                                 The <name> element should contain the name of the vaccine (or active ingredient in
                                    the case of subordinate <substanceAdministration> elements used to record components
                                    of a vaccine). Note that the brand name should be represented as a translation of
                                    the code element.