(Source-theage.com)
Contact tracers have identified a cooling tower in Melbourne’s west as the suspected source of a deadly Legionnaires’ disease outbreak. This outbreak has resulted in the death of an elderly woman and has grown to include 70 confirmed and suspected cases.
Tragic Death and Rising Cases
A woman in her 90s passed away on Tuesday after contracting Legionnaires’ disease. Victorian Chief Health Officer Dr. Clare Looker reported that the disease is spreading through the Laverton North and Derrimut areas of Melbourne. The elderly woman was admitted to the hospital in a severely ill condition and died shortly after.
“Our condolences are with her family,” Dr. Looker said. She urged individuals with symptoms such as a cough and fever to seek medical advice immediately.
Hospitalizations and Intensive Care
Dr. Looker stated that 59 people have been hospitalized due to the outbreak, which includes 60 confirmed cases and 10 suspected cases. Several patients are in intensive care. The majority of those affected were exposed to the disease, a rare form of pneumonia, between July 5 and 20, with symptoms appearing on or after July 15.
Investigation and Disinfection Efforts
Health authorities have inspected and disinfected 41 of the 100 cooling towers in the affected areas, with plans to visit another 15 sites. Contact tracers narrowed their focus to Derrimut and Laverton North after analyzing patients’ movements over the past 10 days using specialized mapping software. The common exposure sites identified were large, open industrial areas, not the usual crowded public spaces.
“It is unexpected when we get it in industrial areas…they’re not typically places where lots of the public will go,” Dr. Looker noted. “This is an unusual outbreak we are dealing with. We’re trying to keep our investigation as broad as possible.”
Awaiting Test Results
While investigators suspect one industrial cooling tower is responsible for the outbreak, they are awaiting test results, which could take up to 10 days, to confirm its precise location.
“There’s a high probability that we have visited the tower and disinfected it,” Dr. Looker said, based on compelling epidemiology and the crossover of case locations.
Historical Context and Weather Factors
This outbreak is the most significant in Victoria since the 2000 Melbourne Aquarium incident, which led to 150 people falling ill and four deaths. Authorities believe Melbourne’s cold weather has contributed to the spread of the disease beyond the usual 500-meter radius. Dr. Looker explained that thermal inversion patterns in mid-July could have caused the disease to spread further.
Air scientists are also investigating whether wind patterns played a role in the wider geographical spread, potentially extending several kilometers from the contaminated cooling tower.
Vulnerable Populations and Symptoms
The incubation period for Legionnaires’ disease is two to 10 days. It spreads not from person to person, but through inhaling small water droplets containing the Legionella bacterium. People over 40, smokers, and those with weakened immune systems are particularly vulnerable.
Royal Melbourne Hospital associate professor Megan Rees highlighted that, in addition to a cough and fever, symptoms can include muscle aches, confusion, and in rare cases, kidney impairment. Some individuals may be asymptomatic, but the disease is detectable through a urine test and treatable with antibiotics. Severe cases may require intensive care and dialysis.
Public Health Advisory
Premier Jacinta Allen urged Victorians experiencing any symptoms associated with Legionnaires’ disease to seek urgent medical attention. “This is a really terrible illness and can cause death,” she said, expressing her condolences to the family of the deceased woman.
This ongoing investigation underscores the critical importance of monitoring and maintaining industrial cooling systems to prevent future outbreaks of this deadly disease.
