Another infection in the San Antonio area caused by Legionella bacteria is giving physicians renewed reason to keep Legionnaires' disease in mind. And that awareness, an infectious disease expert says, is the best thing physicians can do to diagnose it.
The San Antonio Express-News reported last week that Brooke Army Medical Center had confirmed its third case since August of infection from Legionella, the bacteria that can cause the severe form of pneumonia known as Legionnaires' disease. All three cases were civilian staffers at the medical center, according to the report. None had contracted Legionnaires' disease.
San Antonio infectious disease specialist Charles Lerner, MD, a consultant to the Texas Medical Association's Committee on Infectious Diseases, tells Texas Medicine the key to diagnosing a Legionella infection is simply to be aware of it.
"The doctors have to be thinking about the possibility of Legionella. And we don't do it as a matter of routine," Dr. Lerner said. "It's one of the overlooked areas when people do workups on patients."
Prevention of a Legionella infection, though, is "almost impossible," Dr. Lerner says. According to the Centers for Disease Control and Prevention (CDC), Legionella bacteria live in fresh water and mostly spread when people breathe in contaminated water droplets in the air.
"Legionella is ubiquitous in the environment. It's in the water, and it's in the soil," Dr. Lerner said. "It's not at all a rare cause of infection, and it's spread by ingestion as well as inhalation."
But while the organism itself is ubiquitous, Dr. Lerner says, "The infection is not. The more immunocompromised you are, the more likely you are to get the infection. … Perfectly healthy people can get it, but it's more common in people who are immunologically compromised."
CDC says about 1 in 10 people who get Legionnaires' disease will die from it. But antibiotics can treat it. Most who get it will require hospitalization.
Legionella bacteria also can cause Pontiac fever, which causes symptoms similar to a mild case of the flu, according to the CDC.
More information about Legionnaires' disease is available at the CDC's Legionella page.