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.

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.