Chicago tracking July increase in Legionnaires' disease

CHICAGO (AP) - Chicago public health officials say cases of Legionnaires' disease have increased this month.

The Chicago Department of Public Health is tracking the cases and also advised local healthcare providers to consider it for patients with symptoms of respiratory disease.

Legionnaires' disease is caused by bacteria that live in fresh water. It is spread when someone breathes in water droplets containing bacteria and typically does not spread from person-to-person.

People who are older than 50, who smoke or have smoked and those with chronic lung disease or weak immune systems are at a higher risk of Legionnaires' disease.

Symptoms include cough, shortness of breath, fever, muscle aches and headaches. In Chicago, authorities have counted 49 cases of Legionnaires' disease in the first three weeks of July - three times more than the same period in 2020 and 2019.

Of those, 15 people were admitted to an intensive care unit and two died.

The department says Legionnaires' disease is seasonal, increasing from June to October each year. But building shutdowns and lower use of water systems can allow the bacteria to grow in water systems.

Closures associated with the COVID-19 pandemic may have contributed this year. But the department hasn't identified any common source of infections so far.

Commissioner Allison Arwady says the bacteria's growth and spread can be prevented by cleaning water systems, cooling towers, whirlpools and fountains.