When the news broke recently that a deadly outbreak of Legionnaires' Disease had killed 10 people in New York City, many were left scratching their heads asking themselves what this new disease was and how to avoid it.

There’s nothing new about Legionnaires’ Disease, however. The first recognized cases of Legionnaires' Disease occurred in Philadelphia, Pennsylvania, back in 1976. In fact it got its name at an American Legion convention after attendees started coming down with pneumonia and fevers topping 107 degrees. The case was sensationalized across the United States, much like news organizations did in 2014 when they reported on Ebola. Up to 14 people had already been reported dead, with countless others fighting for their lives in the hospital. The scary part? The disease couldn't be identified in lab tests, and there was no way to track the thousands of Legionnaires that had attended the conference.

Legionnaires' Disease is caused by Legionella bacteria and is treated effectively with the right antibiotics. People that are immunocompromised, such as the elderly or patients undergoing chemotherapy are the ones who carry the biggest risk.

It doesn't pass from person to person, so don't worry about obsessively washing your hands. Instead, most people get it from a common source that holds the bacteria, such as contaminated aerosols from cooling towers, hot tubs, showers and faucets or drinking water.