Cook County Department of Public Health

Flu, or influenza, is a contagious respiratory virus that affects the respiratory system and spreads easily....

Opioids are a family of drugs related to opium, including heroin, fentanyl, morphine, codeine, and others...

Syphilis is a sexually transmitted disease (STD) that can have very serious complications when left untreated...

West Nile virus is a serious disease most commonly spread by infected mosquitoes. Mosquitoes become infected...