FluSurv-NET on FHIR Use Cases

Owned by Mike Flanigan
Last updated: Dec 06, 2022
4 min read

  • Use Case 1: Hospital-based influenza case detection and minimum data elements

This use case will identify patients hospitalized with laboratory-confirmed influenza among residents of the FluSurv-NET catchment area (defined by patient county of residence) for active population-based surveillance. The cases are reported along with minimum patient-level data and transmitted to the FluSurv-NET surveillance officers in the relevant state/local jurisdiction. Minimum data elements include state and county of residence, patient age or date of birth, sex, race/ethnicity, hospital admission date, positive influenza testing data (test type, test result, test date), influenza type and subtype (if available), and key indicators of disease severity such as ICU admission, mechanical ventilation, in-hospital death, and length of hospital stay. In addition, all cases are geocoded using address of residence (if available) to obtain the census tract of the patient’s residence.

  • Use Case 2: Hospital-based clinical influenza surveillance

This use case focuses on the more detailed clinical surveillance data collected in FluSurv-NET by site
surveillance officers. Patient-level data from EHRs about persons hospitalized with influenza include health history (underlying conditions, tobacco, alcohol, substance use), clinical course, viral and bacterial codetections, findings from chest imaging, diagnoses, vaccination, and treatment. This use case will include person-level clinical data elements that are currently collected in FluSurv-NET on a standardized case report form for all identified cases. Current case report form included as Appendix 1. Not all of the current data elements may be reachable in a FHIR-based approach; proposed solutions should recognize that this may evolve over time and surveillance officers may still need to conduct medical chart review for some data elements.

  • Use Case 3: Influenza Disease Burden Project

Because testing for influenza and other respiratory viruses is done at the discretion of the clinician and testing practices may vary widely among facilities and over time, some people hospitalized with influenza may not be recognized and diagnosed. To better estimate the full burden of influenza, CDC collects additional information from FluSurv-NET hospitals on the proportion of patients with acute respiratory illnesses (ARI) who are tested for influenza, SARS-CoV-2, and RSV [Appendix 2]. This use case will focus on obtaining data on respiratory viral testing practices for CDC’s influenza disease burden project and transmitting it directly to CDC throughout the season. This project collects anonymized patient-level data on persons hospitalized with ARI (based on ICD-10 diagnosis codes) along with information about whether or not the patient was tested for influenza, SARS-CoV-2, or RSV and if so, the test result and test type used for all tests performed (patients may be tested multiple times). Additional data elements include state, age, race/ethnicity, week of admission, ICD-10 discharge diagnoses, and if possible, whether the patient had been admitted to the ICU or died during the hospital stay.

  • Optional Use Cases 4-5 : Hospital-based surveillance for other respiratory viruses

This use case will focus on collecting equivalent data to Use Cases 1-2 on patients who test positive for SARSCoV-2 (the virus that causes COVID-19) or Respiratory Syncytial Virus (RSV). Public health surveillance through COVID-NET and RSV-NET is conducted in the same sites as FluSurv-NET, collects many of the same data elements, with some additional data elements specific to these viral illnesses. The current case report forms for COVID-19 and RSV are included as Appendix 4 and 5.

 

  • Optional Use Case 6: Influenza vaccine effectiveness evaluation

FluSurv-NET sites participate in occasional evaluations of influenza vaccine effectiveness using what is called a test-negative study design, where patients who test negative for influenza serve as controls for influenza positive cases in an epidemiologic case control study. This use case will focus on collecting equivalent person-level data as in Use Cases 1 and 2 on control patients who test negative for influenza. Influenza negative controls are often further matched to influenza positive cases in time or on other person or clinical characteristics. The contractor will work with CDC and other subject matter experts to clarify study design for control selection if this use case is optioned.

 

  • Optional Use Case 7: Death ascertainment project

To fully understand the mortality associated with influenza, FluSurv-NET sites match hospitalized influenza cases against data from electronic death registration systems (EDRS) at state vital records offices (VROs) to identify deaths that occur within 60 days of hospital discharge from an influenza-associated hospitalization. FluSurv-NET also captures the location of death and listed causes of death (ICD-10 codes or free text entries, varies by jurisdiction) for all FluSurv-NET cases who die in or out of the hospital [Appendix 3]. This use case will focus on methods to improve the automation of data linkage and matching between the records of patients hospitalized with influenza and local ERDS using FHIR.

 

  • Optional Use Case 8: Vaccine verification with immunization information systems

To better understand the impact of influenza vaccines on the clinical course of patients hospitalized with influenza, FluSurv-NET sites verify influenza vaccination information from the patient medical record against state immunization information systems. This use case will focus on methods to improve automation of data linkage and matching between the records of FluSurv-NET cases hospitalized with influenza and state/local immunization information systems using FHIR.