Health authorities have issued a measles alert for north Brisbane after six people were confirmed to have contracted the highly contagious disease.

Six people have contracted measles in north Brisbane, but authorities are unable to say where the outbreak of the highly contagious disease originated from.

Metro North Public Health Unit have issued a health alert for people who visited the North Lakes Aquatic Centre on May 16, a car show at the Rocklea showgrounds on May 9 and the Mercure Hotel at North Quay on May 8 and 10.

The alert has also been issued for spectators at the Nitro Circus event at the Brisbane Entertainment Centre on May 15.

Physician Madhu Chatterji said two infectious people also visited the Redcliffe Hospital on May 11 and 21.

“There is no known link to any other identified case of measles,” Dr Chatterji said.

“Public Health is ensuring that infection control measures are in place and will continue with contact tracing to limit further spread of the disease.”

A measles viral infection causes fever, cough and a runny nose before a red spotty rash and sore eyes develop a few days later.

Occasionally measles has dangerous complications.

It is spread by tiny droplets in the air or by contact with infected secretions from the nose or mouth.

In March 2014 the World Health Organisation announced that measles had been eliminated in Australia, verifying that no local strain of measles was circulating in the community and effective surveillance systems were in place to rapidly detect and respond to cases.