The New York State Department of Health (NYSDOH) announced that five new cases of Legionnaires’ disease had been confirmed in the cluster affecting upper Manhattan, increasing the number of people sickened to 27.

Three of the cluster’s victims have been hospitalized, and one person has died. The illness has infected residents of southern Washington Heights and northern Hamilton Heights.

The New York City Department of Health and Mental Hygiene (DOHMH) first alerted the public about the cluster on July 11, when eight people were confirmed with the disease. The patients have ranged in age from younger than 40 to older than 80, and the majority are older than 50. The individual who died was older than 50 but wasn’t diagnosed early.

Cooling towers suspected
Officials are “actively looking” for the source of the upper Manhattan cluster, DOHMH Commissioner Dr. Mary T. Bassett said, and “we worry about cooling towers.” They are the suspected cause of the cluster.

Inspectors took water samples from 20 cooling-tower systems from buildings between 145th and 155th Streets. The city already has treated the towers’ water, according to Dr. Demetre Daskalakis, deputy commissioner of Disease Control. Several building owners were ordered to increase the use of biocides to kill Legionella, the bacteria that causes Legionnaires’ disease.

Regulations ‘ignored’
Recent data released by the DOHMH suggests that building owners are flagrantly ignoring regulations put into place three years ago to prevent the spread of Legionnaires’ disease.

According to the DOHMH “Annual Report on the Status of Primary Indicators Associated with Cooling Towers” provided to, 6,447 cooling towers were inspected last year. The city issued 75,822 violations — an average of nearly 12 violations for each tower checked. Of those, 5,496 violations were considered public health hazards — meaning the property owner(s):

  • didn’t clean the tower when it was found to have high levels of Legionella;
  • hadn’t taken a recent sample to test for Legionella, or
  • didn’t have a plan to clean it regularly.

People at increased risk
“While most people exposed to Legionella don’t get sick, individuals ages 50 and above – especially those who smoke and have chronic lung conditions – are at a higher risk,” Bassett said. “This disease is very treatable with antibiotics. I encourage anyone with symptoms of Legionnaires’ disease to seek care early.”

Other people more susceptible to infection include:

  • heavy drinkers of alcoholic beverages
  • people with compromised immune systems
  • recipients of organ transplants
  • individuals who are on specific drug protocols (corticosteroids, to name one).

Watch for symptoms
Officials continue to warn people who live, work or travel through the area to be vigilant because someone who is infected might not yet be presenting symptoms, because of the disease’s two-week incubation period.

“It’s really important if you’re feeling sick to get attention,” Daskalakis said.

If you are feeling flu-like symptoms, it’s recommended you see your health-care provider immediately out of an abundance of caution.

Similar to other pneumonia types
Legionnaires’ disease is similar to other types of pneumonia, and its symptoms can resemble those of flu, such as:

  • cough
  • difficulty breathing
  • fever
  • muscle aches
  • headaches
  • gastrointestinal symptoms, such as nausea, vomiting, and diarrhea.

More on Legionnaires’ disease

Legionnaires’ disease is a severe type of pneumonia (lung infection). According to the Centers for Disease Control and Prevention (CDC), an estimated 25,000 cases of pneumonia due to Legionella bacteria (Legionella pneumophila) occur yearly in the U.S. Only 5,000 cases are reported, however, because of its nonspecific signs and symptoms.

One in 10 patients infected with Legionnaires’ will die from the disease.

Legionella bacteria are contracted by inhaling microscopic water droplets, usually in the form of mist or vapor. The bacteria, which grow best in warm water, are found primarily in human-made environments.

Where do Legionella live?
Legionnaires’ disease clusters and outbreaks have been linked to numerous sources, such as:

  • cooling towers of air conditioning systems
  • large plumbing systems
  • water systems, such as those used in hospitals, nursing homes, and hotels
  • hot-water tanks and heaters
  • showers and faucets
  • swimming pools
  • hot tubs and whirlpools
  • equipment used in physical therapy
  • mist machines and hand-held sprayers
  • decorative fountains.