Michigan Flu Surveillance

Each week during influenza season (October through May), MDCH reports the estimated level of influenza activity in the state to the Centers for Disease Control and Prevention (CDC). The five levels, from lowest to highest, are:

  • No activity: No laboratory-confirmed cases of influenza and no reported increase in the number of cases of influenza-like illness (ILI).
  • Sporadic: Isolated laboratory-confirmed influenza cases or a single influenza outbreak has been reported, but no increase in ILI activity.
  • Local: Outbreaks of Influenza or increases in ILI cases and recent laboratory-confirmed influenza in a single region of the state.
  • Regional: Outbreaks of influenza or increases in ILI and recent laboratory confirmed Influenza in at least 2 regions of the state.
  • >Widespread: Outbreaks of influenza or increases in ILI cases and recent laboratory-confirmed influenza in over half the regions of the state.

Weekly Influenza surveillance information is available by visiting the Michigan Flu Focus Newsletter.

Additional information about Influenza can be found at the Centers for Disease Control Influenza Center