It is hard to believe that Legionnaire’s Disease was first recognized after an outbreak at the American Legion convention in Philadelphia in 1976. This disease seldom gets the same attention today as it did then, but it is still around. In fact, the rate of reported cases of Legionnaire’s Disease nearly quadrupled between 2000 and 2015 and it is suspected to be under-diagnosed.

The disease is caused by a bacterium that colonizes in air conditioners, cooling towers, hot water tanks and other places where there may be standing water. People get infected by inhaling mist or aerosolized spray from those areas. The disease is not transmitted from one person to another. This means that if there is an outbreak the place to look is some common exposure to water supplies and air conditioners. Many patients ask about room humidifiers and I usually recommend against them. Patients that have humidifiers on their home heating systems need to be aware of the potential for contamination.

Symptoms of Legionnaires’ Disease include fever and chills, cough, shortness of breath and difficulty breathing, headache which may be severe at times, muscle aches and soreness, chest pain may be present in the more complicated cases, and lastly, fatigue, nausea and diarrhea complete the array of symptoms. Obviously, these same symptoms may occur with many viral infections as well.

Making the diagnosis of Legionnaire’s Disease is important since common antibiotic therapy can be curative. The usual and quickest way to diagnose the disease is with a urine test looking for antibodies.