Influenza Activity Classifications
Tracking Flu Activity for You
We rely on reports from a sentinel surveillance network of doctors, hospitals, and others who have agreed to report flu cases. Public health authorities do not require providers to report flu cases, so we do not know the exact flu numbers.
From the sentinel surveillance network and other resources, we prepare a Weekly Flu Surveillance Report.
How We Classify Flu Activity
There are various types of influenza classifications. To identify laboratory-confirmed cases, we organize cases by the following:
No Activity: No laboratory-confirmed cases of influenza and no reported increase in the number of cases of influenza-like illness.
Sporadic: Small numbers of laboratory-confirmed influenza cases or a single laboratory-confirmed influenza outbreak have been reported, but there is no increase in cases of influenza-like illness.
Local: Outbreaks of influenza or increases in influenza-like illness cases and recent laboratory-confirmed influenza in a single region of the state.
Regional: Outbreaks of influenza or increases in influenza-like illness and recent laboratory-confirmed influenza in at least two but less than half the regions of the state with recent laboratory evidence of influenza in those regions.
Widespread: Outbreaks of influenza or increases in influenza-like illness cases and recent laboratory-confirmed influenza in at least half the regions of the state with recent laboratory evidence of influenza in the state.
How We Report Flu Data
We use the above classification criteria developed by CDC to classify flu activity in Texas.
The weekly report also includes laboratory test results showing what types and subtypes of flu are circulating in Texas, the estimated level of flu-like illnesses occurring, and the number of pediatric flu-associated deaths.
View Flu Reports near you and throughout the United States.