Everything You Need to Know About Legionnaires’ Disease

Everything You Need to Know About Legionnaires’ Disease

Learn more about this potentially deadly form of pneumonia.

You may have heard of Legionnaires’ disease, but you might not know what it is.. Legionnaires’ disease is a rare and serious form of bacterial pneumonia caused by the Legionella bacterium. So where does it get its name? The disease was discovered in 1976 when people got sick after attending an American Legion Convention in Philadelphia.  

The bacterium is not contagious. Instead, it spreads when you inhale mist or vapor (droplets of water in the air) that has been contaminated by the bacteria. While the bacteria are unlikely to be hiding in your home’s shower or air conditioner, large, complex water systems like those of a hotel or apartment building are a different story. In places where the water system is contaminated by Legionella, showers, air conditioners, even hot tubs and decorative water fountains can expose you to Legionnaires’. New York City health officials believe that cooling towers, which hold water for air conditioning units, were the source of one Legionnaires’ outbreak in 2015.

When Legionnaires’ is most dangerous

Legionnaires’ disease sends between 8,000 and 18,000 people in the United States to the hospital each year, according to the Centers for Disease Control and Prevention (CDC). While the disease is serious, the death rate is about 10 percent overall. Ironically, the hospital is one place where you’re more likely to pick up the condition, along with other health care facilities.

The CDC released a report in June 2017 that analyzed data from outbreaks in 20 states and New York City in 2015. It found that 76 percent of the jurisdictions had outbreaks in a health care setting—a hospital, clinic or nursing home.

The spread of Legionnaires’ in a health care setting is especially problematic because the elderly, people with compromised immune systems and people who already have certain conditions like diabetes and some cancers are at higher risk. In these health care-related cases, the report found that the death rate was 25 percent.

Symptoms and treatment

The most common symptoms of Legionnaires’ disease include fever, cough and chills. Other symptoms could be headaches, body aches or diarrhea. Symptoms generally take between two days and two weeks to develop. However, not everyone exposed to the disease-causing bacteria gets sick.

Most cases of Legionnaires’ disease are treated with oral antibiotics, though more severe cases might require an IV. Treatments run between seven and 21 days, and patients usually begin feeling better between three and five days after the onset of symptoms.

What can you do?

Since Legionnaires’ most often happens in public water systems, there’s not a lot you can do. If you live in an apartment building, you can ask your building manager if the building has a water management system that discourages the growth of legionella. And, if you’re at higher risk, you might want to avoid public water sources like hot tubs and decorative fountains. The CDC tracks Legionnaires’ disease outbreaks on its website.