Two separate LA Fitness locations in Orange County are undergoing investigation by the Florida Department of Health after four reported cases of Legionnaire’s disease cropped up among club members.

It has not yet been proven that the disease was contracted at the clubs, but so far membership at LA Fitness has been the only unifying factor linking the afflicted. The club has sent a notice to patrons to be on the lookout for signs of the disease.

Investigators were sent to the clubs to obtain water samples last week, but results will not be seen for about two weeks, Florida Department of Health spokesperson Kent Donahue told the Orlando Sentinel.

In the meantime, the clubs in question have been asked to increase the chlorine levels in the spa areas and to add an extra filter in the shower facilities.

Information from the CDC says Legionnaire’s is most often contracted through a contaminated water or air conditioning system, especially an enclosed system like those used in hot tubs, where the legionella bacteria thrive.

Legionnaire’s manifests in pneumonia-like symptoms such as coughing, shortness of breath, fever, muscle and headaches. Those most at-risk include anyone 50 years of age or older, or those with compromised immune systems.

There have been two other confirmed cases of Legionnaire’s at LA Fitness locations in Central Florida in recent year. In 2008, the bacteria were found at a club in South Downtown Orlando, and in 2010 in a club in the Waterford Lakes Area.

There was also a positive test for the bacteria at Florida Hospital Orlando in late 2015.

Per Donahue, an Ocoee LA Fitness investigated for the bacteria in April turned negative results.

Courtney Cameron is Editorial Assistant of Athletic Business.