Michigan Influenza Hospitalization Surveillance Project (IHSP)

The CDC’s Influenza Hospitalization Surveillance Network (FluSurv-NET) provides population-based rates of laboratory-confirmed influenza-associated hospitalizations among children and adults from October 1st through April 30th of the following year. Michigan participates in FluSurv-NET as an Influenza Hospitalization Surveillance Project (IHSP) state for Clinton, Eaton, Genesee, Ingham, and Washtenaw Counties.

A case is defined as a person who:

  • is a resident in the defined catchment area
  • is hospitalized
  • tests positive for influenza by a laboratory test within 14 days prior to or during hospitalization

FluSurv-NET is CDC’s source for important data on hospitalization rates associated with flu. FluSurv-NET also provides demographic and clinical information including age, sex and underlying medical conditions among persons hospitalized with flu. Data gathered are used to estimate age-specific hospitalization rates on a weekly basis and to describe characteristics of persons hospitalized with influenza illness, as reported in CDC’s FluVIew.