(CBS) The numbers are staggering: 12 deaths, dozens more sick in one month.
The illness is Legionnaires disease and it’s at a veterans’ home in Quincy, Illinois.

How could this happen? CBS 2’s Dana Kozlov investigates.

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About 400 Illinois veterans, some sick, others in need of assistance, go to the facility to live late in life. But the sprawling, post-Civil War facility is now the site of a large Legionnaires disease outbreak, caused by a bacteria born and spread through water.

“Imagine a really, really bad flu that just doesn’t seem to get any better,” said Illinois Director of Public Health Dr. Nirav Shah.

Since August 21, 54 veterans living at the home have been diagnosed with the illness. Of those, twelve have died.

“Part of the challenge for this outbreak was it coincided with normal, seasonal respiratory illness amongst the residents,” said Illinois Department of Veterans’ Affairs spokesperson Ryan Yantis.

“We haven’t identified the precise source and unfortunately we may never,” Dr. Shah said.

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U.S. Senator Dick Durbin finds it alarming.

“We’re worried that this building and the plumbing and some of the problems there may be making it more difficult to make it safe,” Durbin said.

Yantis says the home’s staff, along with state veterans’ and health officials acted quickly once the first cases were diagnosed. They shut off the water, turned off fountains and brought in bottled water.

“Every best effort was made by the home staff, our agency and our agency partners in response to this effort,” Yantis said.

Senator Durbin wants to make sure that’s enough.

“I’m asking the VA to take a look so they can join us in an effort to make sure this is a safe facility,” Durbin said.

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There have been no new cases since September 11, but health officials say there is the possibility there could be more.