New Virus Outbreak In New York: What Is Legionnaires' Disease?

New York City is currently experiencing an outbreak of Legionnaires’ disease, local health authorities said.

The illness is a type of pneumonia caused by bacteria that can grow in hot water called Legionella, according to the Centers for Disease Control and Prevention (CDC).

"Legionnaires’ disease can be caused by plumbing systems where conditions are favorable for Legionella growth, such as cooling towers, whirlpool spas, hot tubs, humidifiers, hot water tanks, and evaporative condensers of large air-conditioning systems," the New York City Department of Health and Mental Hygiene (NYC Health) said in a statement.

Like other types of pneumonia, Legionnaires' symptoms include cough, shortness of breath, fever, muscle aches and headaches.

The disease, which can result in lung failure and death, requires treatment with antibiotics, and it can be treated successfully in most cases, according to the CDC.

A milder version of Legionnaires' disease called Pontiac fever causes flu-like symptoms, but those who contract it do not have signs of pneumonia.

People can contract Legionnaires' when they breathe in droplets of water in the air containing Legionella.

Most "healthy" people do not get sick even after being exposed to the bacteria, the CDC said.

However, people with weak immune systems, smokers and those aged 50 and above are at higher risk of getting sick from Legionella exposure.

People do not spread Legionnaires' disease and Pontiac fever to other people, but it is possible under rare circumstances, according to the CDC.

Reducing the risk of Legionella growth and spread is key to preventing Legionnaires' disease, the health agency said.

"Building owners and managers can do this by maintaining building water systems and implementing controls for Legionella," the CDC explained.

At least 19 people have been diagnosed with Legionnaires' disease since May 3, NYC Health announced Wednesday. Among the infected, one person has died, while eight more people have been hospitalized.

In light of the Legionnaires' outbreak, NYC Health has advised people with flu-like symptoms to contact a physician immediately.

"While most people exposed to the bacteria do not get sick, Legionnaires’ disease can cause severe illness or be fatal for those at higher risk... That’s why it’s crucial that you seek health care as soon as you experience flu-like symptoms," health commissioner Dr. Ashwin Vasan said.

NYC Health sampled the cooling towers in the affected areas and found that four of them had tested positive for Legionella.

Health inspectors will follow up to ensure compliance with disinfection protocols.