Health authorities in the Australian state of Queensland are bracing for a major measles outbreak which could also affect tourists.

On Wednesday the authorities estimated the number of infected people could be around 4,500 after an infected paramedic, 32, visited four hospitals and a tourist site while he was contagious.

He is now severely ill in hospital.

A person with measles, which causes fever and a burning rash all over the body, is contagious for four days before displaying symptoms.

Queensland's chief medical officer Dr. Jeannette Young and Dr. Brad McCall, director of Queensland Health's public health unit, warned southeast Queensland faced another serious measles scare.

"We know that one in three adults who contracts measles will end up in hospital," Dr. Young said.

She urged people to get vaccinated against the disease.