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A lightweight REST-based access layer for standard HL7-defined data models. Read the spec

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The FHIR Immunization Resource provides information about a patient's immunizations, including the vaccine administered and details regarding the administration.

The Immunization resource corresponds to the following Common Clinical Data Set (CCDS) Elements: Immunizations.

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Immunization Search Interaction

Relative URL FHIR Interaction HTTP Method Action
/Immunization?[parameter=value] Search Get Retrieves Immunization resources that meet the specified search criteria

The search interaction enables the client to query for all immunizations documented for a given patient. The client, having established the patient in question, now wishes to retrieve the list of that patient's immunizations, and can futher refine the query by the date administered. Currently, Epic's sandbox supports the following query parameters:

Parameter Name Parameter Type Description
_id Reference Search for Immunization resources using one or more server ids (equivalent to one or more Get /Immunization/{ID} requests)
patient Reference Search for Immunization resources for a specified patient ID.
date Date Further refine a search for a given set of Immunizations on a patient by specifying a date or date range in XML format (YYYY-MM-DD) for when the Immunization was administered or last documented.
Query Result
/Immunization?patient=Tbt3KuCY0B5PSrJvCu2j-PlK.aiHsu2xUjUM8bWpetXoB Retrieve Immunization resources for Jason Argonaut.
/Immunization?patient=Tbt3KuCY0B5PSrJvCu2j-PlK.aiHsu2xUjUM8bWpetXoB&date=gt2016-03-01 Retrieve Immunization resources for Jason Argonaut administered after March 1, 2016.

Immunization Read Interaction

Relative URL FHIR Interaction HTTP Method Action
/Immunization/{ID} Read Get Retrieve details about Immunization ID

The read interaction enables the lookup of an Immunization resource by a constant server ID. The read interaction allows clients to store only the server ID, and with a single request, retrieve the most up-to-date information about an immunization. Read interactions typically begin with a client having previously established a relationship, often through querying for Immunizations through the search interaction.


When things go wrong, the Epic EHR responds with an error code and a human-readable description to describe the incorrect submission. Currently, the error code is not included in the REST version of the specification, but it is provided here for your reference. These codes are meant for developer use only - they should not be presented to end users. Instead, your application should interpret the codes and provide user-friendly resolution steps when data cannot be filed.

FHIR Errors come in two flavors:

  • Fatal Errors cause the response to contain no results and are usually due to requests from the client processed as invalid - missing or invalid data in the request, unauthorized access, or expired content in the system.
  • Warning Errors accompany a successful response and are used to indicate that part of a request could not be fulfilled - for example, if a status is unknown, but the request can be fulfilled, the API will return the data and indicate that part of the request couldn't be understood.

FHIR Error Codes

Error Code Severity Description Example
4100 Fatal The resource request contained an invalid parameter Invalid parameter such as a non existent patient ID: AllergyIntolerance?patient=foo
4101 Warning Resource request returns no results A request for data that was otherwise valid but no information was documented or found (i.e. a patient with no pertinent implanted devices, or a demographic search where no patients met the search criteria).
4102 Fatal The read resource request contained an invalid ID Invalid Resource ID: AllergyIntolerance/foo
4107 Fatal The read resource request has been merged Requesting a Patient which has been merged - in this event, in addition to the error response, we will respond with an HTTP Redirect status. To browsers and many HTTP clients, the redirect will be transparent.
4110 Fatal No parameters are provided in the search request An invalid search request such as : AllergyIntolerance?
4111 Fatal Required search parameter missing from request A request missing a required parameter (such as the patient): Condition?category=diagnosis
4112 Fatal The resource request contained an invalid combination of parameters A search containing multiple different patient ID: AllergyIntolerance?patient=[ID 1]&patient=[ID 2]
4113 Fatal Session ID for cached search results has expired. Making a request for previously accessed paginated search results after the search has expired.
4115 Fatal Required search parameter has an invalid value An invalid parameter required for searching: Condition?Patient=[ID]&category=foo
4117 Warning No CVX code for Immunization resource Request for an Immunization resource without a documented CVX code.
4118 Fatal User not authorized for request Request data that the authenticated user is not allowed access to view (i.e. a patient asking for data about a stranger's allergies).
4119 Warning Additional data may be present for patient Request data while authenticated as an authorized patient or patient proxy. Inidicates that data available to the patient may not be the complete medical record within the system.
4122 Warning An unknown query parameter was supplied by the client A request with dateWritten on a resource for which the parameter is ignored.
A request with parameter zzzzzz on any resource.