New York health officials announced Wednesday that the death toll from an outbreak of Legionnaires' disease in New York City has risen to eight.

The respiratory bacterial infection is usually spread through mist that comes from a water source, like cooling towers, air conditioning or showers. However, it cannot be transmitted from person to person.

The symptoms -- which include headache, fatigue, loss of appetite, fever, chills, confusion and diarrhea -- tend to appear between 2 to 10 days after significant exposure to the bacteria.

Altogether, 97 people have been diagnosed with Legionnaires, a severe form of bacterial pneumonia, but only 92 received hospital treatment, reports CNN. So far, 48 of those hospitalized have been treated and released.

Health officials discovered that the outbreak began in the South Bronx after five of 17 cooling towers inspected for legionella bacteria tested positive. The five towers were at Streamline Plastic Co., Lincoln Hospital, the Concourse Plaza shopping center near Yankee Stadium, the Opera House Hotel and a Verizon office building. Since then, all five have been decontaminated and are under watch by health officials.

Officials added that the city's drinking water, pools, fountains, water towers and buildings cooled with air conditioners pose no risk to public safety.

In most cases of Legionnaires' disease, the bacteria can be traced to plumbing systems that give way to legionella growth, such as whirlpool spas, hot tubs, humidifiers, hot water tanks, cooling towers, and evaporative condensers of large air-conditioning systems.

NYC Mayor Bill de Blasio announced on Monday that a "comprehensive package" of new legislation would be introduced to stop and prevent future outbreaks. He also said that outbreaks of the disease "have become far too common over the past ten years, and the City will respond not by only addressing an outbreak as it occurs, but with a new plan to help prevent these outbreaks from happening in the first place," according to USA Today.

"People have to understand that this is a disease that can be treated -- and can be treated well if caught early," de Blasio said last Thursday, reports MSNBC. "The exception can be with folks who are already unfortunately suffering from health challenges, particularly immune system challenges. But for the vast majority of New Yorkers, if they were even exposed, this can be addressed very well and very quickly so long as they seek medical treatment."