This messaging specification provides notes for required (non-optional) fields for each of the non-optional segments. For each segment the segment table defines the applicable constraints on usage for its fields for this specification (see Section 3.2 Message Element Attributes for a description of the columns in the Segment Attribute Tables.) All the relevant conformance statements and general usage notes are located at the end of each table. MSH - The MSH Segment is used to define the intent, source, destination, and some specifics of the syntax of the message. This segment includes identification of message delimiters, sender, receiver, message type, timestamp, etc. Table 5.2.1: Message Header Segment (MSH) Field Name Seq DT Len Usage Cardinality Value Description/Comments Set Field Separator 1 ST 1 R [1..1] Conformance Statement: CN-004: MSH.1 (Field Separator) SHALL contain the constant value '|'. Encoding Characters 2 ST 4 R [1..1] Conformance Statement: CN-005: MSH.2 (Encoding Characters) SHALL contain the constant value '^~\&'. Sending Application 3 HD 227 R [1..1] This field uniquely identifies the sending application among all other 61 applications within the network enterprise. The network enterprise consists of all those applications that participate in the exchange of HL7 messages within the enterprise. A public health agency (PHA) with the authority to send HL7 case notifications to CDC should use a unique Object Identifier (OID) in this field to indicate the specific PHA system from which the case notification data is being sent. Each PHA sending system should have its own unique OID. (Refer to TA and Training Resource Center at for further resources).
This messaging specification provides notes for required (non-optional) fields for each of the non-optional segments. For each segment the segment table defines the applicable constraints on usage for its fields for this specification (see Section 3.2 Message Element Attributes for a description of the columns in the Segment Attribute Tables.) All the relevant conformance statements and general usage notes are located at the end of each table. MSH - The MSH Segment is used to define the intent, source, destination, and some specifics of the syntax of the message. This segment includes identification of message delimiters, sender, receiver, message type, timestamp, etc. Table 5.2.1: Message Header Segment (MSH) Field Name Seq DT Len Usage Cardinality Value Set Description/Comments Field Separator 1 ST 1 R [1..1] Conformance Statement: CN-004: MSH.1 (Field Separator) SHALL contain the constant value '|'. Encoding Characters 2 ST 4 R [1..1] Conformance Statement: CN-005: MSH.2 (Encoding Characters) SHALL contain the constant value '^~\&'. Sending Application 3 HD 227 R [1..1] This field uniquely identifies the sending application among all other applications within the network enterprise. The network enterprise consists of all those applications that participate in the exchange of HL7 messages within the enterprise. A public health agency (PHA) with the authority to send HL7 case notifications to CDC should use a unique Object Identifier (OID) in this field to indicate the specific PHA system from which the case notification data is being sent. Each PHA sending system should have its own unique OID. (Refer to TA and Training Resource Center at for further resources). 61
PHIN_Messaging_Specification_for_Case_Notification_v3%200_Release_2_2_20180401.docx