100 Cases of Legionnaires Disease in Victoria

Legionella pneumophila bacteria which are responsible for causing the pneumonic disease Legionnaires' disease in a 1978 electron microscope image. Francis Chandler/CDC via AP

Victorian health authorities have confirmed that Legionnaires’ disease has spread to at least 100 people in the state.

The Victorian Department of Health noted there had been a “significant increase” in cases across metropolitan Melbourne in the past week.

The majority of those who have contracted the disease have been sent to hospital, with a “number of admissions” in intensive care with severe pneumonia.

“There have been 100 confirmed and 10 suspected cases notified since Friday 26 July, mostly in adults aged over 40 years,” the advisory states.

“All cases have visited or reside in metropolitan Melbourne.”

Legionnaires’ disease is a lung infection that is caused by the bacteria Legionella. This bacteria can be found in lakes, creeks, and hot springs, along with artificial systems like cooling towers, plumbing systems, hot water tanks, and heaters.

In this case, Victorian authorities have identified a cooling tower in Melbourne’s west as the likely source of the disease.

Chief Health Officer Dr. Clare Looker said Legionella bacteria was found in a sample from the cooling tower on Aug. 5

“This is a direct result of our rapid investigation, which saw the likely source located, tested, and disinfected, within a matter of days,” she said in comments provided to the Epoch Times.

“The tower was visited early on in our investigations, on July 30. And it was disinfected within 24 hours of that visit.”

So far, two people have died of Legionnaires’ disease, including a woman in her 90s and a man in his 60s.

The Victorian Department of Health regards Legionnaires’ disease as an “urgent notifiable condition,” meaning doctors and pathology services are required to immediately notify any detected cases to authorities.

In metropolitan Melbourne, health authorities have reported a “significant increase” in case numbers since July 26, 2024.

Victorian authorities regard those aged over 40 years, smokers, and individuals with chronic lung disease, or weakened immune systems to be at higher risk of infection.

Underlying health conditions including chronic heart, liver, kidney disease, and diabetes are also risk factors.

The health department (pdf) noted Legionnaires’ often appear within two to ten days as a chest infection, with symptoms including chills, fever, cough, headache, muscle aches, and pains.

Less common symptoms can include nausea, confusion, vomiting, diarrhea, and in some cases, impairment of the kidney.

“Legionnaires’ disease is spread by breathing in fine droplets of water that contain Legionella bacteria. It is not commonly spread from person-to-person or by drinking contaminated water,” the health department said.

Cooling tower operators in Metropolitan Melbourne have been advised to make sure they have complied with cooling tower testing, servicing, and auditing.

Doctors have been advised to request “urgent urinary antigen testing” if Legionnaires’ disease is suspected.

“As a priority, order Legionella culture and PCR on sputum or other respiratory fluid samples. Serology can be requested on blood at symptom onset and 3 to 6 weeks later,” doctors are advised.

“Early diagnosis and treatment with appropriate antibiotics are important.”

1 in 10 Will Die: CDC

In the U.S., the Centers for Disease Control and Prevention (CDC) says that 10 percent who fall ill with the disease will die due to complications from their illness.

“For those who get Legionnaires’ disease during a stay in a healthcare facility, about 1 out of every 4 will die,” the CDC states.

“Healthy people usually get better after being sick with Legionnaires’ disease, but they often need care in a hospital.”

Legionella bacteria was first identified in 1976 during an outbreak at an American Legion convention in Philadelphia, Pennsylvania, where 221 people became ill and 34 died.

In NSW, a smaller outbreak in February led to two men in their 60s and one woman in her 70s contracting the disease, all of whom recovered.

NSW Health concurs with the CDC that 10 percent of those who fall sick with Legionnaires’ disease are at risk of dying.

“People can become very sick with pneumonia; most people recover, but around 10 percent of patients die,” NSW Health states.