(CBS) — Two people have contracted Legionnaires Disease in west suburban Naperville. WBBM’s Bob Roberts reports that public health officials are trying to assure it doesn’t spread.

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The Legionnaires bacteria has been traced to a hot tub at the LA Fitness in Naperville, on Freedom Drive at Naperville Road.

DuPage Health Department spokesman Jason Gerwig says no one will be using the hot tub for a while.

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“They have been more than cooperative with us in cleaning the area that was in question. As in any case with this we shut it down to make sure that this wasn’t spread and it was confined to the location it was discovered,” said Gerwig.

Gerwig says the tub must go through two rounds of testing that comes back “clean” before it can reopen — although the rest of the club remains in operation. Gerwig refused comment on the conditions of those who were taken ill, or whether they have recovered.

DuPage County Health Department says both the victims were male and “medically stable.”

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“In this case it got into the water system and somehow colonized it and that’s the concern,” said Kevin Dixon, Director of the DuPage County Health Department.