|Articles|May 28, 2019

NJ Documents 5 Deaths in Ongoing Legionnaires' Disease Outbreak

According to the New Jersey Department of Health, there have been 22 confirmed cases of Legionnaires’ disease in individuals who reside in or visited Union County.

The New Jersey Department of Health (NJDOH) has announced an investigation into a Legionnaires’ disease outbreak that turned deadly in 1 county.

According to a statement issued by the health agency late Friday afternoon, there have been 22 confirmed cases of Legionnaires’ disease in individuals who reside in or visited Union County. As of May 23, 2019, there have been 5 deaths recorded in the outbreak, all of which occurred in older adults with “other significant medical conditions.”

NJDOH is working alongside the US Centers for Disease Control and Prevention (CDC) and local health departments to investigate this cluster. Each year there are between 250-350 cases of Legionnaires’ disease in the state, however a cluster is considered an outbreak where 2 or more individuals fall ill following exposure to Legionella bacteria in the same place or at the same time. In this particular outbreak, all 22 individuals fell ill between March 8th and May 13th.

At this time, NJDOH is conducting epidemiologic and environmental investigations to identify possible sources of exposure to the bacteria. At this point in time, state health officials have not identified a specific exposure location, but the ongoing investigation has identified some potential sources and remediation has begun.

Health officials are conducting environmental sampling for Legionella and recommending environmental remediation strategies to prevent further transmission of Legionnaires’ disease. However, the statement notes that it is possible that there are multiple sources of bacteria in this outbreak.

According to New Jersey Health Commissioner Shereef Elnahal, MD, the risk of acquiring the disease is low for the average person. “This is a continuing investigation. The risk to any resident of, or recent visitor to Union County is very small,” he said in a press release.

Elnahal’s statement is reflective of the fact that most people exposed to Legionella do not develop Legionnaire’s disease. However, people over 50, smokers, and those with weakened immune systems are at increased risk for developing the disease.

Individuals may be exposed to Legionella via breathing in aerosolized water from cooling towers, cooling misters, fountains, and plumbing systems. The bacteria can be found in water systems of any type, but people cannot contract Legionnaires’ by drinking water. Additionally, home air conditioning units do not use aerosolized water and are therefore not at risk for Legionella growth.

According to the CDC, illnesses due to Legionella are usually reported in the summer and early fall. Last summer a cluster of infections were detected in both Washington Heights and the Bronx in New York City. Later in the summer, an outbreak was detected in Hampton, New Hampshire, which health officials found to be linked to a hot tub spa.

However, NJDOH reports that investigations into Legionnaires’ clusters are highly complex and that it is often not possible to determine the source of infection.

Elnahal further notes that individuals who live in the county should report any symptoms that are consistent with Legionnaires’ to their health care provider. As symptoms can take up to 2 weeks to develop, it is advised that individuals who develop symptoms within 2 weeks of visiting Union County should also seek medical attention. The disease is typically treatable with antibiotics, and health care providers in Union County have been alerted to be cognizant that patients may have been exposed to the bacteria.

This is an ongoing investigation and the NJDOH will provide more information as it becomes available.

For the most recent case counts in the Legionnaires’ disease outbreak in Union County, New Jersey, visit the Contagion® Outbreak Monitor.


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