Influenza Surveillance

While influenza is not a reportable disease in Illinois, IDPH examines reports from many health care sites throughout the state. These sites include physician offices, emergency departments, and other clinics that report acute illness with influenza-like illness, and institutional settings such as nursing homes and prisons that report outbreaks. Accordingly, IDPH monitors disease trends and influenza activities as they occur on a weekly basis.

A detailed surveillance report can be found here. This weekly surveillance report summarizes regional and state influenza data. All data in this report are provisional and may change as additional reports are received. Data are obtained from providers and health care facilities who voluntarily report influenza-like illness visit data from their facilities and submit clinical specimens for testing at IDPH laboratories. This is a sample which provides a picture of influenza activity in Illinois and not inclusive of every case of influenza in Illinois.

Vaccination is the best way to protect against influenza infection. All Illinois residents aged 6 months and older should be vaccinated annually.

  • Flu vaccination can keep you from getting sick with flu.
  • Flu vaccination can reduce the risk of flu-associated hospitalization, including among children and older adults. 
  • Flu vaccination is an important preventive tool for people with chronic health conditions.
  • Vaccination helps protect women during and after pregnancy. Getting vaccinated also protects the developing baby during pregnancy and for several months after the baby is born.
  • Flu vaccination also may make your illness milder if you do get sick.
  • Getting vaccinated yourself also protects people around you, including those who are more vulnerable to serious flu illness, like babies and young children, older people, and people with certain chronic health conditions.

For questions, contact the IDPH Communicable Disease Section at 217-782-2016 or dph.influenza@illinois.gov.

Additional reports on influenza in Chicago can be found on the City of Chicago Influenza Website