An outbreak of measles at the University of Queensland (UQ) is likely to spread across Brisbane after the latest patient caught an international flight, Queensland Health warns.

The Metro North Public Health Unit (PHU) said a seventh student had been diagnosed with the highly contagious virus in five weeks.

The latest patient travelled on Singapore Airlines flight SQ235, which arrived in Brisbane on Saturday, August 15.

PHU physician Dr James Smith said measles was infectious for about four days before a rash developed.

"None of the seven cases realised they were highly infectious when on campus and in the community," he said.

"This means we expect to see further measles cases from contact with these individuals.

"Symptoms usually start around 10 days after contact, but can occur between seven and 18 days after contact with an infectious person."

The PHU is advising students who are unwell to avoid the university campus, part-time work, shopping centres and social events.

"If you do need to seek treatment, it is important to call the medical practice first to say you could have measles, so that staff can take precautions to avoid spreading the disease to others," Dr Smith said.

He said early symptoms of measles were similar to the flu and include a fever, cough, runny nose and dry, itchy eyes.

The virus can cause serious complications such as pneumonia and encephalitis (inflammation of the brain).