Syndromic Surveillance

More information about syndromic surveillance.

Emergency Room Visits by Syndromic Surveillance Category in Maine

What is syndromic surveillance?

Syndromic surveillance is the collection of health data based on syndromes. A syndrome is a pattern or collection of symptoms related to an illness. Maine CDC collects this information from medical facilities. It allows Maine CDC to look for disease outbreaks and health trends.

Syndromic surveillance works with traditional case reporting. It does not identify individual cases of interest or concern. The data shown here are rough estimates. They do not represent exact counts of disease or condition cases.

How does syndromic surveillance work?

All hospitals in Maine (except Togus VA hospital) report information about emergency room (ER) visits to Maine CDC. This report happens within hours after the visit. This information is “de-identified”. This means it does not include:

  • Names
  • Street addresses
  • Social security numbers

It does include:

  • Age
  • Sex
  • Race/ethnicity
  • Zip code where the patient lives
  • Chief complaint (the reason for the ER visit)
  • Diagnosis
  • Notes taken by triage nurse

Maine CDC uses computer algorithms to search the text of these reports. The algorithm categorizes ER visits into syndromes. For example, an ER visit might have a chief complaint that reads “cough and fever”. The algorithm finds that this visit has flu and/or respiratory illness symptoms. It categorizes this visit under flu and/or general respiratory illness. It adds up the number of visits in this category into daily tallies and graphs. Over time, these graphs show trends or “spikes” of outbreaks.

How is syndromic surveillance different than case reporting?

Syndromic surveillance does:

  • Provide information faster than traditional case reporting.
  • Give public health agencies rapid notification that an outbreak may be happening.
  • Provide information about conditions and diseases not reported by law (PDF). This could include heat-related illness, injuries, or the common cold.

Syndromic surveillance does not:

  • Replace traditional case reporting (hospitals and doctors reporting individual cases of disease).
  • Provide data as precise and accurate as traditional case reporting.
  • Find individual cases of disease with 100% accuracy.

Read more in Syndromic Surveillance: What Data Users Need to Know (PDF).

Email syndromic@maine.gov with questions about the data.

Other Resources

For more public health information about environmental hazards and data, visit the Maine Tracking Network

For more public health information about drug and alcohol use and overdoses, visit the State Epidemiological Outcomes Workgroup and the Maine Drug Data Hub