Concern rises after study finds 50% of homes tested in Hamilton Township positive for legionella bacteria

PHILADELPHIA (CBS) -- Officials in Hamilton Township, New Jersey, are concerned about bacteria in the water, especially in homes and businesses serviced by Trenton Water Works. A study found that 50% of homes tested were positive for the legionella bacteria, which can cause legionnaires disease. 

Trenton Water Works is aware of the problem and has been working on the issue since 2020. 

It is safe to drink, but there are concerns certain residents might be at risk. This is a warning about legionnaires disease. People can get infected when they inhale contaminated water droplets. 

Health officials say the risk is low, but they want the 50,000 people who live in Hamilton Township to know there's a potential danger.

The legionella bacteria has been found in an abnormally high number of homes in Hamilton Township, Mercer County, which is close to Trenton.

The health department says of the 20 random homes sampled, half were contaminated with the bacteria that causes legionnaires disease, a type of pneumonia. 

People are usually infected after breathing aerosolized water, small droplets containing the bacteria. 

"People are concerned," Hamilton Township Mayor Jeffrey Martin said. 

Martin says there have been four cases of legionnaires in the past two years in the township. Two of the cases were this month and one of the four patients died. 

Trenton Water Works say it's working with health officials to identify the cause and continues to test, flush and clean its systems. 

"We're trying to figure out what's causing it, where it's coming from and why it's happening at a higher percentage of Hamilton than it is even in other municipalities that are serviced by Trenton Water Works," Martin said. 

"The risk is real," health official Chris Hellwig said. "This is something that we want everyone to take seriously." 

Hellwig says legionnaires causes flu-like symptoms and can be treated with antibiotics. 

"Most healthy people this is not going to be an issue, but those who have underlying health conditions or who are older, really do need to take proactive caution," Hellwig said. 

People who live in Hamilton Township are advised to take precautions including: 

• Setting your water heater to a minimum of 120 degrees reduces the bacteria
  
• Flush faucets and showers, let them run for at least three minutes if they're not frequently used
• Clean and replace showerheads and water filters routinely

Health officials say there are probably many more homes and people impacted and that the investigation is continuing to determine the source of the bacteria.

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