Sick with Legionnaires?
Call (612) 337-6126
Elliot Olsen has decades of experience representing people harmed by Legionnaires’ disease. If you or a family member contracted Legionnaires’ disease at Chicago’s Mercy Hospital and Medical Center, please call (612) 337-6126 for a free consultation.


Two cases of Legionnaires’ disease have been reported at a Chicago hospital, and the Illinois Department of Public Health (IDPH) is investigating.

Health officials said two patients with the disease were possibly exposed at Mercy Hospital and Medical Center, where Legionella bacteria, which causes Legionnaires’ disease, was reported in the facility’s water system.

The general public is not at risk, according to the IDPH, and their investigation is confined to the hospital, which is located at 2525 S. Michigan Avenue in the Bronzeville neighborhood.

Investigators for the IDPH and the Chicago Department of Public Health (CDPH) have collected environmental samples for laboratory testing, according to a news release from the IDPH.

Remediation efforts – including flushing the water system, altering or replacing water fixtures, and installing filters on sinks to eradicate the spread of the disease – have begun.

Hospital officials also said staff is conducting active surveillance of patients to identify other potential Legionnaires cases.

Mercy Hospital made headlines last Nov. 19, when a mass shooting took place at the hospital. Four people were killed: a Chicago police officer, a pharmacy resident, the shooter’s ex-fiancee, who was an emergency surgeon, and the shooter, who shot himself.

Legionnaires info

According to the Centers for Disease Control and Prevention (CDC), an estimated 25,000 cases of pneumonia due to Legionella bacteria (Legionella pneumophila) occur yearly in the U.S. Only 5,000 cases are reported, however, because of its nonspecific signs and symptoms.

Approximately one in 10 patients infected with Legionnaires’ disease – also called legionellosis or Legionella pneumonia – will die from the infection.

High-risk groups
Anyone can get the disease, but those at the highest risk of infection include:

  • people 50 years old or older
  • smokers (current or former)
  • heavy drinkers of alcoholic beverages
  • people with chronic lung disease (such as chronic obstructive pulmonary disease [COPD] or emphysema)
  • people with weakened immune systems (those suffering from conditions such as diabetes, cancer, kidney failure, or infected with HIV)
  • organ-transplant recipients (kidney, heart, etc.)
  • individuals following specific drug protocols (for instance, corticosteroids)

Even relatively healthy individuals have been known to contract the disease, although less typically.

Common symptoms
The symptoms of Legionnaires’ disease look like other forms of pneumonia or even the flu, which is why so many cases go unreported every year. Early symptoms can include the following:

  • chills
  • fever (potentially 104 degrees or higher)
  • headaches
  • loss of appetite
  • muscle aches.

After the first few days of the disease presenting, symptoms can worsen to include:

  • chest pain when breathing (called pleuritic chest pain, due to inflamed lungs)
  • confusion and agitation
  • a cough, which may bring up mucus and blood
  • diarrhea (about one-third of all cases result in gastrointestinal problems)
  • nausea and vomiting
  • shortness of breath.

(Note: There is also a mild form of Legionnaires’ disease called Pontiac fever, which can produce similar symptoms that include fever, chills, headache, and muscle aches. Pontiac fever doesn’t infect the lungs, however, and symptoms usually manifest within two to five days.)

Legionella sources
The bacteria, which grow best in warm water, are found primarily in human-made environments. Outbreaks have been linked to numerous sources, such as:

  • cooling towers of air conditioning systems
  • large plumbing systems
  • water systems, such as those used in hospitals, nursing homes, and hotels
  • hot-water tanks and heaters
  • showers and faucets
  • swimming pools
  • hot tubs and whirlpools
  • equipment used in physical therapy
  • mist machines and hand-held sprayers
  • decorative fountains.

People also can contract Legionnaires’ disease by the aspiration of contaminated drinking water – that is, choking or coughing while drinking can cause water to go down the wrong pipe into the lungs. It’s also possible to contract Legionnaires’ disease from home plumbing systems, although the vast majority of outbreaks have occurred in large buildings because complex systems allow the bacteria to grow and spread more quickly.