Given the task definition and input, reply with output. Generate an explanation for the given claim using the provided supporting material from the paragraph. Please consider the following points while generating an output. 1) The claim will always have supporting proof in the paragraph, and the paragraph will have a clear point of view supporting the claim. 2) There can be instances where direct correlation to the claim is not available. Make use of the sentences in the paragraph to provide a corresponding output supporting the claim. 3) The explanation should be at least one and at most twelve sentences long.

Paragraph: The Illinois Department of Public Health said Friday the three people were all patients at Northwestern Medicine Central DuPage Hospital in Winfield, about 30 miles (48 kilometers) west of Chicago. One person was an inpatient, while the other two had outpatient visits. IDPH said the three patients also had other possible sources of exposure in the 10 days before their symptoms began, so the hospital may not be the source. The department says it's working with the hospital to further investigate the cases and will be conducting more tests of facility's water. IDPH says the hospital is providing information to patents and employees who may have been affected. Most healthy people don't get Legionnaires' disease after being exposed to Legionella bacteria, which occurs naturally in the environment. The Centers for Disease Control and Prevention recommends public health officials conduct investigations into the source of Legionella whenever two or more cases are possibly associated with a health care facility within 12 months of each other. Claim: Legionnaires' cases may be linked to Chicago-area hospital.
State health officials are investigating whether three cases of Legionnaires' disease are linked to a suburban Chicago hospital.