This page contains charted data (updated weekly) from the 93 Michigan health care providers that have volunteered to participate in the Centers for Disease Control and Prevention (CDC) U.S. Influenza Sentinel Provider Surveillance Network.  Click here for a map of the surveillance sites. These Michigan clinicians have volunteered to provide the CDC and the Michigan Department of Community Health (MDCH) with information about visits to their practices due to influenza-like illness (ILI). 

For surveillance purposes, ILI is defined as a fever of 100°F or higher accompanied by a cough, sore throat, or both. While these symptoms are common to many diseases, large and sudden increases in the number of ILI cases are often due to influenza. Taken together, these data and other influenza surveillance indicators provide a broad picture of influenza activity in Michigan. 

It is important to note that ILI data provided from the Influenza Sentinel Providers can be used to determine where and when influenza-like illness activity is occurring, but not the total number of ILI or influenza cases statewide.