Increasing syphilis rates in north Queensland have prompted public health groups to urge young people to get tested and practise safe sex.
The Townsville Hospital and Health Service recorded 33 cases of the sexually transmitted infection before September this year, including one that was transferred to an unborn baby from its mother.
Townsville Public Health Unit (TPHU) director Dr Steven Donohue says the number of cases, which grew from 25 in the same period last year, was concerning.
He said an untreated case could have serious consequences, including a higher risk of HIV infection.
"Syphilis is highly infectious and often has no symptoms," he said.
"It usually needs a blood test to detect."
The infection of unborn babies from their mothers - known as congenital syphilis - can lead to miscarriage, stillbirth and infant death.
The Townsville Aboriginal and Islander Health Service (TAIHS) says gay and bisexual men and young Aboriginal and Torres Strait Islander people are most at risk of getting the infection.
But he said it can be avoided through the proper use of condoms.
"We are urging sexually active young people to come to their local health services," senior medical officer Dr Theunis Kotzee said.
The health warning comes almost a month after the Queensland Aboriginal and Islander Health Council (QAIHC) warned of the worst syphilis outbreak seen in Australia's northern indigenous communities in 30 years.
They say 500 Aboriginal or Torres Strait Island Queenslanders have been infected since 2010.
Indigenous people living in remote northern areas were 300 times more likely to be affected than other Australians, they said.
