Thousands of Ballarat residents who holiday or visit the Bellarine Peninsula risk picking up a dangerous flesh-eating ulcer, but health authorities are at a loss to explain how it spreads.
The Buruli ulcer, also known as the Bairnsdale ulcer, is at epidemic levels on the Bellarine and Mornington Peninsulas and medical experts are calling for urgent funding for research in to how the disease is transmitted.
Barwon Health infectious diseases expert Associate Professor Daniel O’Brien has treated many Ballarat residents who have come in to contact with the bacteria Mycobacterium ulcerans, which causes “severe destructive lesions of skin and soft tissue”, while visiting the Bellarine Peninsula.
“The community is facing a worsening epidemic, defined by cases rapidly increasing in number, becoming more severe in nature, and occurring in new geographic areas,” Associate Professor O’Brien wrote in the Medical Journal of Australia.
In 2016, there were 182 new cases of Buruli ulcer in Victoria, the highest ever, but in 2017 there had already been 236 cases reported by November 11.
Last year Associate Professor O’Brien treated about 110 people with Buruli ulcer, compared to about 20 to 40 in the years before.
He called for research funding to be made available so authorities can find out how the bacteria spreads.
“We know you are at risk of this infection if you go to the Bellarine or Mornington Peninsulas and you have to be in those areas to get it, but we don’t know how you actually get it.
“It is a significant illness and what I would like is, when people from Ballarat come to the Bellarine to holiday, that they can be best protected. How can I protect them if I don’t know how they get it in the first place?”
In the most severe cases, surgery is needed.
The Geelong-based expert is bracing to see another influx of people with the slowly growing ulcers. The disease is typically acquired during the warmer months but with a four to six month incubation period, patients usually seek treatment from May to November.
Most patients present with a slowly growing ulcer on one of their limbs that looks like a pimple or mosquito bite which is usually painless. Occasionally it can present as a nodule or lump under the skin or as a painful red swelling over a join that is similar to cellulitis.
“Lesions most commonly occur on exposed body areas, suggesting that bites, environmental contamination or trauma may play a role in infection, and that clothing may protect against disease,” Associate Professor O’Brien said.
Theories about the spread of M. ulcerans include mosquitoes, spray irrigation, environmental disturbance such as floods and road construction, biting aquatic insects and possum faeces.
“Despite being recognised in Victoria since 1948, efforts to control the disease have been severely hampered because the environmental reservoir and mode of transmission to humans remain unknown. It is difficult to prevent a disease when it is not known how infection is acquired,” Associate Professor O’Brien said.
“It is only when we are armed with this critical knowledge that we can hope to halt the devastating impact of this disease through the design and implementation of effective public health interventions.”