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NJDOH Investigates Spike in Legionnaires’ Disease Cases in Middlesex, Union Counties

Union County Middlesex County

By: Richard L. Smith 

Middlesex and Union counties in New Jersey are currently facing an uptick in Legionnaires’ disease cases, prompting the New Jersey Department of Health (NJDOH) to launch a thorough investigation.

AdResidents in the affected areas are urged to be vigilant and seek medical evaluation if they develop symptoms suggestive of Legionnaires’ disease.

As of November 6, the NJDOH has been alerted to a total of 21 individuals from Middlesex County and 20 individuals from Union County who have fallen ill and tested positive for Legionella, the bacteria responsible for causing Legionnaires’ disease.

The onset of symptoms occurred between August 3 and October 24, 2023. Thankfully, no fatalities have been reported so far.

On average, both counties typically see six to eight confirmed Legionnaires’ disease cases each year during the August to October period.

NJDOH is actively collaborating with local health departments in Middlesex and Union counties to investigate these cases and identify potential sources of infection.

In mid-October, the NJDOH issued alerts to local health departments, healthcare providers, and public health partners in the area to highlight the increased number of reported cases.

To date, investigators have not identified a common exposure among the affected individuals.

Legionnaires’ disease, a form of pneumonia, presents symptoms that can resemble those of COVID-19 and other respiratory illnesses, including fever, chills, cough, shortness of breath, chest pain, muscle aches, and headaches.

A definitive diagnosis can only be made through tests ordered by a medical professional. Fortunately, Legionnaires’ disease is treatable with antibiotics.

Given that symptoms may take up to two weeks to manifest, the NJDOH advises individuals who develop these symptoms within two weeks of visiting Middlesex or Union County to seek medical attention promptly.

Acting Health Commissioner Dr. Kaitlan Baston stressed the importance of early diagnosis, stating, “Early diagnosis is key to effectively treating Legionnaires’ disease.

Although the risk of contracting Legionnaires’ disease if you live in or have recently visited Middlesex or Union counties remains low, individuals who develop pneumonia-like respiratory symptoms should visit their health care provider immediately to be evaluated.”

Generally, healthy individuals exposed to Legionella have a low risk of developing Legionnaires’ disease.

AdHowever, individuals over 50 years of age, especially those who smoke or have specific medical conditions such as weakened immune systems, chronic lung disease, or other chronic health issues, are at an increased risk if exposed to Legionella bacteria.

Importantly, Legionnaires’ disease is not transmitted from person to person. Infection occurs when individuals inhale aerosolized water containing Legionella bacteria.

Sources of aerosolized water can include cooling towers, hot tubs, cooling water misters, decorative fountains, and plumbing systems. Home air conditioning units, whether central or in-window, do not utilize water for cooling and do not pose a risk for Legionella growth.

In rare cases, individuals may become ill if water containing Legionella is aspirated into the lungs while drinking, particularly among those with swallowing difficulties.

Cooling tower systems, commonly found in larger facilities such as public buildings, offices, commercial spaces, universities, hospitals, community centers, and industrial sites, play a crucial role in removing heat from various processes.

However, if not adequately maintained, these systems can release water droplets containing Legionella into the air, putting individuals in the vicinity at risk of exposure.

NJDOH advises owners and operators of cooling tower systems to review their water management and maintenance plans to reduce the risk of Legionella growth and spread.

Collaborating with water treatment consultants to conduct Legionella testing in these systems is recommended. Cooling tower systems that test positive for Legionella should be remediated following CDC guidelines.

Maintaining appropriate biocide (chemical) levels in circulating water is essential, even during low-use periods.

AdIf a cooling tower system hasn't been cleaned and disinfected within the last 12 months (or more frequently if recommended by the manufacturer), immediate scheduling for cleaning and disinfection is strongly advised. Additional guidance can be found on the CDC's website.