FAQ: What is Legionnaires' disease?

At least a dozen people living or working in the Twin Cities suburb of Hopkins were sickened recently by Legionnaires' disease.

As Minnesota health authorities work to find the source of that outbreak and investigate other potential cases, medical analyst Dr. Jon Hallberg on Tuesday told MPR News' All Things Considered about the disease, how you can get it and how it affects the body.

How long have we known about it?

The disease was first identified at an American Legion convention in Philadelphia in 1976. The New York Times has reported that people who attended got sick with the "mysterious symptoms" of pneumonia and high fevers.

What causes the disease?

Legionnaires' is caused by Legionella bacteria, but most people who are exposed don't get sick. The elderly, smokers and people with chronic conditions are at greatest risk.

Is it contagious?

No. The bacteria infect people through tiny airborne water droplets, often coming from large cooling towers or industrial buildings. You need to be exposed to a contaminated source to contract it. You can't get it from a sick person coughing on you.

What are the symptoms?

The disease typically starts with muscle aches, shortness of breath and a headache, Hallberg said. Eventually, it can turn into serious pneumonia.

How common is it?

Minnesota usually has 50 to 60 Legionnaires' cases each year. That's in line with national averages.

What will it take to end the Hopkins outbreak?

Once officials find the source, they'll clean it and the outbreak will be halted. "It's as simple as that," Hallberg said, "but it takes a lot of sleuthing and epidemiology to figure out where it's coming from."

Volume Button
Now Listening To Livestream
MPR News logo
On Air
MPR News