What We Can Do
Who is at Risk?
People 50 years or Older
Those with chronic lung disease (like COPD or Emphysema)
People with weak immune systems or who take drugs that weaken the immune system (such as after transplant operation or chemotherapy)
People with Cancer
People with underlying illnesses such as diabetes, kidney failure, or liver failure
Shortness of Breath
Information from CDC:
In 1976, CDC (in cooperation with other federal, state, and local authorities) launched one of the largest disease investigations in U.S. history following an outbreak of severe pneumonia (lung infection) among the participants of the American Legion Convention in Philadelphia, Pennsylvania. As a result, CDC identified the new bacterium (Legionella pneumophila) that was spread through the hotel’s air conditioning system. On July 27, three days after the convention ended, the first victim died. Within a week, more than 200 people, mostly men, had been hospitalized, and 34 had died. All had attended the convention and stayed at the same hotel.
People can get Legionnaires’ disease when they breathe in mist (small droplets of water in the air) containing the bacteria. One example might be from breathing in droplets sprayed from a hot tub that has not been properly cleaned and disinfected. Outbreaks are most commonly associated with buildings or structures that have complex water systems, like hotels, hospitals, long-term care facilities, and cruise ships. Within these structures, the bacterium can become a health concern when it grows and spreads in human-made water systems, like hot tubs, cooling towers, hot water tanks, large plumbing systems, and decorative fountains. Most healthy people do not become infected with Legionella bacteria after exposure.
HOW IS IT DIAGNOSED?
Specialized laboratory tests are necessary and, unfortunately, may not be available in many hospitals. These include culture on specialized Legionella media. Culture media furnish nutrients for the bacterium. When sputum from the patients is placed onto the culture media, the bacterium grows on the medium and can be identified.
Other tests include direct fluorescent antibody (DFA) in which the bacterium can be stained and becomes visible under a fluorescent microscope. Antibody testing is a blood test in which antibodies that are reactive against Legionella are present in the human body showing that the patient has come into contact with the bacterium previously. Urinary antigen is a test that detects Legionella in the urine
PROGNOSIS / OUTCOME?
If the patient is treated with appropriate antibiotics near the onset of pneumonia, the outcome is excellent, especially if the patient has no underlying illness that compromises his/her immune system. For patients whose immune systems are compromised, including transplant recipients, delay of appropriate therapy can result in prolonged hospitalization, complications, and death.
For those patients who are discharged from the hospital, we have found that many will experience fatigue, loss of energy, and difficulty concentrating for several months after discharge from the hospital. In a long-term study of 122 survivors of Legionnaires' disease in the Netherlands, symptoms of fatigue (75%), neurologic symptoms (such as concentration problems and malaise) (75%), and neuromuscular symptoms (such as joint pain or muscle weakness) (79%) had persisted 17 months later (Lettinga KD, Clin Infect Dis, July 1, 2002). Respiratory tract symptoms were also present, but in lower frequency including cough (48%) and shortness of breath on exertion (38%). It could not be determined whether or not the persistence of these symptoms were due to specifically for Legionnaires' disease or for severe pneumonia, in general.
Serious sequelae, fortunately, are rare. In our experience, most patients will recover completely within one year. If the patients are cigarette smokers, the patients should discontinue smoking.
Many antibiotics are highly effective against Legionella bacteria. The two most potent classes of antibiotic are the macrolides, gemifloxacin, trovofloxacin). Other agents that have been shown to be effective include tertacycline, doxycycline, minocycline, and trimethoprim/sulfamethoxazole.
Erythromycin, the former antibiotic of choice, has been replaced by the more potent and less toxic antibiotics.