McHenry County health officials still are seeking the source and common denominator that led to nine people contracting Legionnaires’ disease between June 7 and July 1.
Those who became ill live in Algonquin, Crystal Lake, Huntley, McHenry, Union and Wonder Lake and range in age from 46 to 82, McHenry County Department of Health spokeswoman Keri Zaleski said Thursday.
None of the victims live in a public facility and each was diagnosed by a physician.
“We are speaking with everyone involved and trying to find what that link might be,” Zaleski said. “We’re looking at water sources. We are looking at the things that are the common sources (of Legionnaires’ disease). It does occur naturally. In most people, if you are young and healthy you don’t have any symptoms. You don’t become ill from it.”
The health department is working with the Illinois Department of Public Health and Centers for Disease Control and Prevention in the investigation.
Legionnaires’ disease is caused by waterborne bacteria inhaled from vapor. The disease occurs more frequently in hot and humid weather, and is caused by a type of bacteria commonly found in the environment. It can become a health concern when it is found in building water systems such as shower heads, hot tubs, fountains, hot water tanks and large plumbing systems, according to a health department news release.
Its symptoms are similar to pneumonia often starting two to 10 days after exposure and include diarrhea, nausea, vomiting, aching muscles, fever and chills. Shortness of breath, coughing, headache, or mental confusion also can be common.
Zaleski urges anyone presenting such symptoms to get tested for Legionnaires’ disease through their health care providers.
“Legionnaires’ disease is not known to spread person to person,” Illinois Department of Public Health Chief Medical Officer Jennifer Layden said. “Most healthy people do not get Legionnaires’ disease after being exposed to Legionella bacteria. Individuals at increased risk of developing Legionnaires’ disease include those older than 50 or who have certain risk factors, such as being a current or former smoker, having a chronic disease, or having a weakened immune system.”
A 2015 outbreak at a Quincy veterans’ home in western Illinois caused the death of 13 residents and sickened dozens more.
Yet, that was a confined population, while McHenry’s cases are spread throughout the county, Zaleski said.
McHenry’s last major Legionnaires’ outbreak was in 2008, but typically a few cases occur each year, she added.
“There have been three outbreaks in the last 15 years or so,” Zaleski said. “Over the past five years there has been an average of five cases per year. This has gotten our attention because the time frame is a month. Our intent is to make sure that this is something on people’s radar.”
For more information, visit cdc.gov/legionella.