HL7 VXU^V04 (Unsolicited Vaccination Record Update)
VXU^V04 transmits a vaccination record update to an immunization information system (registry). The RXA segment carries the administered vaccine (CVX code), dose, and date.
When is VXU^V04 sent?
Sent by an EHR or clinic to a state/regional immunization registry when a vaccination is administered or a historical dose is reported.
Key segments
The segments below are the ones most relevant to VXU^V04. Real messages may carry additional optional segments depending on the sending system’s configuration.
| Segment | Usage | Role |
|---|---|---|
| MSH | Required | Message header: sending/receiving application & facility, message type, control id, version. |
| PID | Required | Patient identification: identifiers (MRN), name, date of birth, sex, address, phone. |
| ORC | Optional | Common order: links the administration to an order; often minimal in VXU. |
| RXA | Required | Pharmacy/treatment administration: the administered vaccine (CVX), dose amount and units, administration date, and information source. |
| RXR | Optional | Pharmacy/treatment route: route and site of administration. |
Example VXU^V04 message
A realistic, well-formed example. Segments are separated by carriage returns; fields by the pipe (|) delimiter.
MSH|^~\&|IMM|HOSP|REC|REC|20240115110000||VXU^V04|MSGCTRL6666|P|2.5.1
PID|1||MRN12345^^^EPIC^MR||DOE^JOHN^A||19800101|M
ORC|RE|||
RXA|0|1|20240115|20240115|140^Influenza, seasonal, injectable^CVX|0.5|mL^milliliter^UCUM||00^New immunization record^NIP001Mapping VXU^V04 to FHIR
See the full field-by-field mapping of VXU^V04 to a FHIR Immunization — including the transforms and gotchas — on the VXU^V04 → US Core Immunization reference page. You can fork that template and run it in the Mapping Builder.
Frequently asked questions
What is an HL7 VXU^V04 message?
VXU^V04 is an unsolicited vaccination record update. It reports an administered (or historical) immunization to a registry, with the vaccine, dose, and date carried in the RXA segment.
What does the RXA segment carry?
RXA carries the administered vaccine code (typically CVX in RXA-5), the dose amount (RXA-6) and units (RXA-7), the administration date (RXA-3), and the information source (RXA-9, e.g. new vs. historical record).
How do I map VXU^V04 to a FHIR Immunization?
Map RXA-5 to vaccineCode (CVX system), RXA-3 to occurrenceDateTime, RXA-6/7 to doseQuantity, and set status to completed. The Interoperall template implements this mapping.
How do I validate a VXU^V04 message?
Paste it into the HL7v2 validator to parse the RXA/ORC structure and check it is well-formed before sending to a registry.