Hospital study finds link between La Niña events and spread of deadly Vibrio vulnificus infection

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a day ago

Anamika Ganju had not seen anything like it in more than 20 years as an intensive care clinician.
Two men in three days had presented to the emergency department with baffling similarities.
Both men, aged around 80, had cuts that had rapidly progressed to grotesque infections, with their skin sloughing away to reveal gaping wounds.
Both had been crabbing in the muddy estuaries of rivers swollen by floodwater that had devastated the Wide Bay region just weeks before.
And to the despair of Dr Ganju and her colleagues, both men were unresponsive to the standard antibiotics used to treat bacterial infections.
"It is pretty devastating," Dr Ganju said.
"You're like, 'Why is this patient so sick? What am I missing? He shouldn't be so sick … with [the] signs and symptoms I'm seeing, they should start getting better."
Analysis of decaying tissue from one of the patients in March 2022 showed it was teeming with Vibrio vulnificus — a flesh-eating bacteria rare enough in the tropical north of Queensland, but almost unheard of in the Fraser Coast region about three hours' drive north of Brisbane.
Vibrio vulnificus was known to thrive on the additional nutrients brought by floodwaters, but Dr Ganju said the scarcity of the infection in the hospital's sub-tropical location meant it was not initially considered a likely diagnosis.
"To be honest, in my career — I've been doing this for 25 years — I had not seen a Vibrio [case] before this," Dr Ganju said.
The medical team pivoted to use ciprofloxacin, an antibiotic known to target Vibrio vulnificus, and both patients underwent operations to remove and replace the decaying flesh.
Three more fishermen presented to the hospital with bacterial infections over the next six months and, by then, the team was on high alert.
Source: Queensland Health
"We would always ask whether there was exposure to … marine water or were they in a boat, and if we got that history we would start the ciprofloxacin [immediately]," Dr Ganju said.
More than one in four patients can die once the infection takes hold, but all five men survived.
The third patient, Hervey Bay fisherman Rodney Drier, required 18 operations and after contracting a fungal infection had his left hand amputated.
He rues the slip of a knife while cutting up a catfish to use as crab bait which had life-changing consequences.
"It ruined my lifestyle … took my life away from me," the disability pensioner said.
Once all patients were discharged in 2022, Dr Ganju and her colleagues recorded their experience in a clinical case report published today in the Rural and Remote Health Journal.
By analysing the frequency of Vibrio vulnificus infections in Queensland, lead author and senior pharmacist Daniel Bermingham found spikes of infections over the past 25 years corresponded with La Niña weather events.
While there were only 86 cases of Vibrio vulnificus infections in Queensland between 1998 and 2023, the number of cases increased nearly fivefold during a La Niña event.
With carbon emissions known to contribute to more frequent and extreme La Niña events, Mr Bermingham said his research showed climate change increased the risk of Vibrio vulnificus infections.
The researchers hope the findings will result in a public awareness campaign of the potentially fatal risks and best practice if the infection is acquired.
"The first aid care that you can provide to yourself … is to get the first aid kit out, give [the wound] a good wash and make sure that you can clean the wound from injury," Mr Bermingham said.
"Get some chlorhexidine or some betadine and put it onto the actual wound and go see the GP or ED if it does tend to get worse."
Allen Cheng, the director of Monash Infectious Diseases at Monash Health in Victoria, was not involved in the clinical case report and does not believe "major changes" to public health messaging are warranted.
However, he agreed the epidemiology, or distribution, of Vibrio vulnificus was becoming more common in subtropical regions due to global warming.
"The case report … is at least a very good reminder to physicians that this [infection] does exist and we may be seeing changes in the epidemiology."
In a statement, Queensland Health says the department issues public health advice about the risks of exposure to floodwaters, particularly around severe weather events.
The Queensland Health guidelines prescribing antibiotics in cases of severe infections were last reviewed in 2024, the spokesperson said.
The guidelines now advise using ciprofloxacin — the antibiotic targeting Vibrio vulnificus — if the patient is exposed to water, including in subtropical regions like Hervey Bay.
As he tends to his orchids, Mr Drier is emphatic that there needs to be improved public awareness of the infection.
"Especially when you see people walking in floodwaters in the streets," he said.
"I think, 'You stupid fools, if only you knew'. One scratch and you've got a bug."