Earlier this month, eight people were diagnosed with Legionnaires’ disease as part of an outbreak within a 20-block area of lower Washington Heights, New York. Now, 16 cases have been confirmed in Washington Heights and Hamilton Heights. The New York City Health Department is currently investigating this occurrence of Legionnaire’s disease.

Seven of the eight affected individuals have been hospitalized. Most of the sick were over 50 years old. There have been no deaths associated with this outbreak.


Legionnaires’ disease (legionellosis) is a form of pneumonia caused by Legionnaires’ disease bacteria (LDB), or Legionella. Water is the primary natural reservoir for Legionella, and dangerous levels of the bacteria can appear in man-made aquatic environments. People can contract Legionnaires’ disease if they breathe in mist or vapor containing the bacteria.

Potential sources:



  • Showers/ hot tubs
  • Cooling towers
  • Water tanks
  • Large plumbing systems
  • Decorative fountains
  • Whirlpool spas
  • Fitness clubs
  • Misting systems


Refer to Walden’s previous blogs for additional information on Legionella regulations and preventative maintenance requirements:

Warm Weather’s Here! Are Your Air Conditioning Systems Preventing Legionella Growth?

Cooling Tower and Evaporative Coolers Issues – What You Need to Know about Legionella Compliance in New York State

Cooling Season is Approaching – Is Your Building Protected From Legionella?

Need Help Making Sure your Facility is Safe?

Walden Environmental Engineering has a team of Legionella prevention experts who can help you prepare and implement your Preventative Maintenance Plan, stay on top of Health Department regulations, and protect your facility against worker illness and potential legal action by preventing Legionella growth.

Please give us a call at (516) 624-7200 to discuss further!