YWCA Evanston/North Shore closed after Legionella bacteria are found

EVANSTON, Ill. (CBS) -- The YWCA in Evanston is closed until further notice after the north suburban city's health department says it found two positive cases of Legionnaires' disease connected to the building.

The city said Legionella bacteria was found in the hot water system at the YWCA Evanston/North Shore, located at 1215 Church St. at Ridge Avenue.

The sign on the door to the YWCA said all "aquatics programming" is canceled, but CBS News Chicago has confirmed the whole YWCA Evanston/North Shore building has been closed until further notice.

The Evanston Department of Health & Human Services wants people who have recently visited this location to be on the lookout for the warning signs for Legionnaires'.

In a letter sent to some YWCA members on Thursday, staff explained that Legionella bacteria was found in their hot water system, and also confirmed they know of at least two positive cases associated with that exposure.

"The bacteria was found in the hot water system, which feeds sinks and showers," the letter said.

The letter said the two pools at the YWCA tested negative for the bacteria. Other areas that are only sourced by the cold-water system, like toilets, were also unaffected.

Legionnaires' Disease is a rare, but severe disease caused by Legionella bacteria—which can lead to pneumonia.

It can spread from inhalation of water vapors, but does not spread from person to person.

Dr. Emily Landon of University of Chicago Medicine said people who recently visited the YWCA Evanston/North Shore and used the water—or did not—should not panic either way.

"So even when we see these Legionella outbreaks associated with exposures in public buildings, it's usually very few people who end up getting sick. If you use these facilities that are affected by this finding of Legionella then, and you are specifically—if you were using warm water from the faucet, or if you were showering, then you probably have had an exposure," Landon said.

Landon added that the gap in time from exposure to symptoms can be long for Legionnaires'.

"Healthy individuals are unlikely to develop illness from this, but that does not necessarily mean that you won't," she said. "If you have had this exposure and you start to get sick. It's usually in about two to 14 days, so it could be quite a long time."

Landon said shutting down the building was the right thing to do until all the bacteria are flushed out.

The Illinois Department of Public Health said it is also involved in the investigation, but had no update at this time.

YWCA officials said Saturday that new .2-micron filters have been installed on nearly all faucets and showers. The filters have a 99.99999% bacteria kill rate.

The temperature of the facility's hot water storage tank also temporarily was increased from 140° to 150° to ensure bacteria in the water were killed. The hot water system temperature has since been returned to 140°, which is generally hot enough to inhibit Legionella growth.

In addition,k chlorine levels in the swimming pool were temporarily increased to enhance water purification for the next three months.

Before the facility reopens, the YWCA is working with a water treatment consultant to develop a waster treatment and maintenance management plan.

The YWCA is expected to reopen in a few days, but a specific date has yet to be determined.

Anyone who recently visited the YWCA in Evanston, and thinks they might have been exposed or are experiencing symptoms, the City of Evanston advises consulting a medical provider for further instructions.

The email sent to YWCA members included a link to CDC information on the disease. 

The YWCA Evanston/North Shore is separate from, and belongs to a separate organization from, the McGaw YMCA at 1000 Grove St. in Evanston—which is not affected by the Legionella concern.