Clostridioides difficile Infection (CDI) Surveillance

What to know

  • The Clostridioides difficile infection (CDI) Surveillance Program collects data for describing incidence and trends of these infections.
  • Public health professionals and healthcare providers can use these data to further public health research and, in turn, health outcomes.

Overview

As part of CDC's Emerging Infections Program (EIP) Healthcare-Associated Infections – Community Interface (HAIC) Activity, the Clostridioides difficile infection (CDI) Surveillance Program identifies and monitors:

  • CDI incidence and burden in communities and healthcare settings.
  • Molecular and microbiologic characteristics of strains causing disease.
  • Trends in disease over time, including changes in strain prevalence.

To collect this information, trained professionals conduct active population- and laboratory-based surveillance in 10 EIP sites.

Public health professionals and healthcare administrators can use these data to further research such as:

  • Identifying risk factors for CDI.
  • Identifying populations to prioritize for vaccines and other prevention measures.
  • Monitoring effectiveness of prevention strategies.

Highlights

Trends in race and sex‎

In 2021, the incidence rate of CDI increased with age. Additionally, rates were higher in women than in men and higher in White persons than in persons of other races.1

What the data shows

  • There were 110.2 cases per 100,000 persons in EIP sites in 2021.
  • Underlying conditions were common among CDI cases.
  • 61% of CDI cases used antibiotics in the prior 12 weeks.1

Explore the data

Access and create data visualizations‎

HAICViz is an interactive data dashboard that provides information included in the reports below as well as case rates and deaths over time.
HAICViz

Annual reports

Publications

See Also: NCBI Collection

About the data

Methods

EIP sites conducting surveillance

California
  • San Francisco County
Colorado
  • Adams, Arapahoe, Denver, Douglas and Jefferson Counties
Connecticut
  • New Haven County
Georgia
  • Clayton, Cobb, DeKalb, Douglas, Fulton, Gwinnett, Newton and Rockdale Counties
Maryland
  • Caroline, Cecil, Dorchester, Frederick, Kent, Somerset, Talbot, Queen Anne’s, Washington, Wicomico and Worcester Counties
Minnesota
  • Benton, Morrison, Olmsted, Stearns and Todd Counties
New Mexico
  • Bernalillo County
New York
  • Monroe County
Oregon
  • Klamath County
Tennessee
  • Davidson County

Case definitions

Incident case

When the following criteria is met for a patient who lives in the surveillance area:

  • A patient with a positive C. difficile toxin assay or a positive C. difficile molecular assay (e.g., PCR) of a stool specimen who did not have a positive specimen in the prior 8 weeks.
    • Patient must be at least 1 year old.
    • For surveillance purposes, an individual may be classified and captured as a new incident case if 8 consecutive weeks have elapsed since their last C. difficile-positive test.

Recurrent episodes

  • Patients with a positive C. difficile stool specimen between 2 and 8 weeks of the last positive specimen.

Duplicate episodes

  • Patients with a positive C. difficile stool specimen less than 2 weeks since the last positive specimen.

Case ascertainment

EIP site staff identify cases based on reports of positive C. difficile toxin assay or C. difficile nucleic acid amplification assay from clinical, reference and commercial laboratories serving residents of the surveillance areas.

EIP site staff record information on additional positive specimens from the same patient to identify and track recurrent or duplicate episodes, as well as new cases.

Data collection

EIP site staff perform a brief medical-record review of all* incident CDI cases to collect the following data:

  • Basic demographic characteristics.
  • Location of stool collection.
  • Healthcare exposures.

EIP site staff do not review records of recurrent or duplicate episodes.

*In Colorado and Georgia (the EIP sites with the largest surveillance populations), EIP site staff review a random sample of incident cases.

Epidemiologic classification categories

  1. Healthcare facility-onset (HCFO) if the positive stool specimen collected is either:
    1. Greater than three calendar days after hospital admission.
    2. In a resident of a long-term care facility.
  2. Community-onset healthcare facility-associated (CO-HCFA) if the positive stool specimen collected is:
    1. Either in an outpatient setting or within 3 calendar days after hospital admission.
    2. In a person with documented overnight stay in a healthcare facility (i.e., hospitalization or long-term care facility stay) in the 12 weeks before stool specimen collection.
  3. Community–associated (CA) if positive stool specimen collected is:
    1. Either in an outpatient setting or within 3 calendar days after hospital admission.
    2. In a person with no documented overnight stay in a healthcare facility during the 12 weeks before the specimen collection.

A portion of cases subsequently undergo a comprehensive medical record review for clinical information and relevant risk factors.

Laboratory characterization

EIP site staff collect a convenience sample of stool specimens from incident CDI cases for whom case report forms have been completed. Stool specimens are sent to reference laboratories for culture. C. difficile isolates obtained from these cultures are sent to CDC for molecular typing and characterization.

Keep Reading: Isolate Bank – C. difficile Infection Tracking

Resources

Case report form for EIP surveillance staff

2024 CDI

More information

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Content Source:
National Center for Emerging and Zoonotic Infectious Diseases (NCEZID)
  1. Centers for Disease Control and Prevention. 2023. Emerging Infections Program, Healthcare-Associated Infections – Community Interface Surveillance Report, Clostridioides difficile infection (CDI), 2021. Available at: [Insert link to the report].