The Cicada Vaccine Forecasting Engine and Guide
0.1.0 - ci-build

The Cicada Vaccine Forecasting Engine and Guide - Local Development build (v0.1.0) built by the FHIR (HL7® FHIR® Standard) Build Tools. See the Directory of published versions

Cicada IG Home

Official URL: http://fhirfli.dev/fhir/ig/cicada/ImplementationGuide/cicada.ig Version: 0.1.0
Draft as of 2026-09-07 Computable Name: CicadaIG

Cicada IG

100% Credit goes to the CDC and their Clinical Decision Support for Immunization (CDSi)

All I've done is take all of their hard work, guidance and expertise and make it computable (well, perhaps it's already computable, I made a computer actually do it).

The CDSi Logic Specification can be found on the CDC CDSi page. The current supporting data version implemented is 4.61-508.

First, a warning: This is not completely FHIR compliant. As part of this was to help myself get more familiar with FHIR Shorthand (commonly known as FSH), there are some "Resources" I've defined (e.g. Antigen Supporting Data and Schedule Supporting Data), that are certainly NOT FHIR. However, they are an accurate representation (at least in JSON) for the data used in the CDC's "CLINICAL DECISION SUPPORT FOR IMMUNIZATION (CDSI): LOGIC SPECIFICATION FOR ACIP RECOMMENDATIONS".

Preparation

  • Technical background on the code generator and build pipeline for anyone interested in working on this themselves.

Immunization Decision Support Forecast Working Group

  • Because I can never find it
  • Official HL7 working group

Logical Specification Concepts

  • There are a number of concepts that are involved in the evaluation and prediction of immunizations. Some of these terms make logical sense, but others do not. Here's a description of some of them. Again, this was all taken from the Clinical Decision Support for Immunization (CDSi).

Processing Model

  • Brief overview of the analysis and forecasting process prior to a detailed discussion.

Evaluate Vaccine Dose Administered

  • Summarizes the steps to evaluate every vaccine within every series to which it applies.

Forecast Dates and Reasons

  • Made it through the evaluation process. Next up, creating the forecast.

Select Patient Series

  • After evaluating and forecasting, we need to pick the best series for each antigen. This covers pre-filtering, prioritization, scoring, and final selection.

    Dependencies and terminology

Package hl7.fhir.uv.extensions.r4#5.3.0

This IG defines the global extensions - the ones defined for everyone. These extensions are always in scope wherever FHIR is being used (built Sat, May 16, 2026 18:32+1000+10:00)

Package hl7.fhir.us.immds#1.0.0

An IG for querying a decision support engine for a personalized immunization forecast. (built Fri, Jun 25, 2021 15:56+1000+10:00)

Package hl7.fhir.uv.tools.r4#1.1.2

This IG defines the extensions that the tools use internally. Some of these extensions are content that are being evaluated for elevation into the main spec, and others are tooling concerns (built Tue, Mar 24, 2026 11:13+1100+11:00)

There are no Global profiles defined

Parameter Value
system-version SNOMED CT[US]

This is an R4 IG. None of the features it uses are changed in R4B, so it can be used as is with R4B systems. Packages for both R4 (cicada.ig.r4) and R4B (cicada.ig.r4b) are available.

Intellectual property

This publication includes IP covered under the following statements.