Queenslanders are being urged to ensure they've had two doses of the measles vaccine after 13 confirmed cases in the state already this year.

Queenslanders have again been warned about the dangers of measles after a man, who travelled to Vietnam, became the latest confirmed case of infection.

It brings the number of confirmed cases in the state this year to 13 - one less than the total number of cases for 2018.

Qld Health confirms 13th measles case

Queensland Health recommends people born after 1965, who have had only one dose of the MMR (measles, mumps and rubella) vaccine, visit their doctor for a free booster.

"Measles is one of the most infectious of all communicable diseases," Dr Rosie Muller from Queensland Health said in a statement on Wednesday.

"Early symptoms include fever, runny nose, lethargy and sore, red eyes."

The infection is spread from person-to-person by tiny droplets created during coughing and sneezing.

A blotchy red rash follows the symptoms and can lead to serious complications, such as pneumonia and encephalitis (inflammation of the brain), Dr Muller said.

On Monday, Dr Jonathan Malo of the health department's communicable diseases branch said the majority of measles cases diagnosed originate from people who travelled overseas.

"(They) then come back to Queensland where the infection can be further spread among those who are not immune," he told reporters.

"It can be a very serious illness and that's why people die all around the world."