A POTENTIALLY lethal tick infection newly identified in Australia has mysteriously emerged on the NSW south coast.
Doctors have revealed the first reported Australian case of human babesiosis, a tick-borne infection that carries a 5 to 10 per cent fatality rate, higher than the death rate from the most common tick bite infections.
The victim was a 56-year-old man from the south coast who died, it is thought, partly as a result of babesiosis.
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His infection was discovered only by chance, when his blood samples were re-checked four months after he had been admitted to Canberra Hospital with serious injuries after a car crash in November 2010.
In a report published today in the Medical Journal of Australia , doctors say the infection probably contributed to his death from multi-organ failure last April.
The report of the first babesiosis case in Australia thought to have been locally acquired had raised ”intriguing questions” about how the infection is spread in Australia, the lead author of the report, Sanjaya Senanayake, of the Australian National University, said.
The likely host or carrier would be a rodent. In the US, where babesiosis has been a not uncommon problem in recent years, the infection tick is carried by the white-footed mouse.
The fact that the babesiosis strain identified from the south coast patient was very similar in molecular type to the US strain suggested it had arrived recently in evolutionary terms, possibly with a rodent migration of about 200 years ago to Australia.
The infection may not have been identified until now because it had never been reported. Many people do not report tick bites and an estimated one third do not even realise the cause of their discomfort, Associate Professor Senanayake said.