New Brunswick

Legionnaires' disease outbreak declared in greater Moncton with 7 confirmed cases

There is an outbreak of legionnaires' disease in the greater Moncton area, with seven confirmed cases of the severe pneumonia in the past month, according to the Office of the Chief Medical Officer of Health.

Public Health is investigating to determine source of the legionella bacteria

Dr. Cristin Muecke was New Brunswick’s acting chief medical health officer in mid-March when the COVID-19 pandemic arrived. She warned physicians tests for the virus were in short supply. (CBC)

There is an outbreak of legionnaires' disease in the greater Moncton area, with seven confirmed cases of the severe pneumonia in the past month, New Brunswick's deputy chief medical officer of health announced on Thursday.

Public Health is working with "multiple partners" to investigate the source of the legionella bacteria, which can be found in both natural bodies of water and man-made water systems, such as large air-conditioning units, said Dr. Cristin Muecke.

Officials believe the cases are related, she told reporters during a news conference in Fredericton.

"What has alerted us to trying to find a common source is that all seven of those cases have been people that are either living or working in the Moncton area and they've all occurred in the last month. So that in and of itself over that time frame and in that limited area is unusual."

Muecke did not provide any other specifics but did say that "most" of the seven cases have been hospitalized and all are reportedly doing well.

Anyone who inhales mist or steam containing the bacteria can develop the disease, also known as legionellosis.

It can be treated with antibiotics but often requires hospitalization and can be fatal if left untreated.

Legionnaires' disease is caused when water contaminated with certain bacteria, shown here in a colourized electron micrograph, are inhaled into the lungs. (Janice Haney Carr/Centers for Disease Control/Associated Press)

"Out of an abundance of caution, we recommend individuals who become ill with pneumonia-like or respiratory symptoms, such as fever, chills, cough, shortness of breath, muscle aches and headache, promptly seek medical care or call 811," the province's health information line, Tele-Care, Muecke said.

"Most healthy people, even when they're exposed to this bacteria, do not develop illness," she said.

According to the Public Health Agency of Canada​​​​, if 100 people are exposed, fewer than five will get sick.

But about 30 per cent of known cases have been fatal, according to the Canadian Centre for Occupational Health and Safety.

Who's most at risk?

Those considered most at risk include people over the age of 50, people with weakened immune systems or chronic diseases, and smokers and alcoholics.

People who work with constructed water systems, such as air-conditioning system maintenance workers, are also considered at increased risk, said Muecke.

Air-conditioning units in homes and cars do not use water to cool, so they don't pose a risk.

Legionnaire's disease is not typically spread person to person and people do not become ill by drinking water containing legionella, she said.

Symptoms usually start between two and 14 days after exposure to the bacteria and can also include mental changes, such as confusion, disorientation, hallucination and memory loss.

Complete recovery can take several months.

Legionnaires' disease can be diagnosed based on clinical symptoms and confirmed by testing samples from the lungs, blood and urine.

In New Brunswick, 28 cases of legionnaires' disease were reported to the provincial government between 2015 and 2018.

Across Canada, the average number of reported cases is generally less than 100 per year, but the actual number of cases is thought to be much higher, according to the Public Health Agency of Canada.

Bacteria can survive for months

Legionella can be found in rivers, lakes, ponds and streams around the world, but it's "quite rare" for people to contract the disease from natural sources, said Muecke.

Most people who become ill have been exposed through man-made sources, such as air conditioners, cooling towers, whirlpools, spas and decorative fountains.

Cases of legionnaires' disease have occurred in many different settings, including homes, commercial buildings, spas, cruise ships and health care facilities, according to the Public Health Agency of Canada.

The bacteria can survive for several months in a wet environment and multiply in the presence of algae and organic matter.

Proper cleaning and maintenance of mist-producing devices, such as shower heads, hot tubs, whirlpool bathtubs and humidifiers can help reduce the risk.

There are about 35 legionella species known to produce the disease.

Legionella bacteria can also cause Pontiac fever, a milder illness that resembles the flu. It doesn't infect the lungs and can clear on its own, without any treatment.

The name legionnaires' disease comes from an outbreak of pneumonia that killed 29 people at an American Legion convention in Philadelphia in 1976.


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