Six new cases of measles are being linked to a passenger on an AirAsia flight D7214 from Kuala Lumpur to Melbourne on March 7.

The new cases include a baby who was too young to be immunised and five adults ranging in age from 20 to 60.

All of them were in the international baggage area of Melbourne Airport when the flight arrived about 9:30am.

The initial case of measles was tracked to an Australian man in his 40s who became unwell on the flight and went straight to hospital where he was diagnosed.

Measles is a highly infectious viral disease which can cause serious illness, including pneumonia and other complications in the very young and very old.

The symptoms are similar to the common cold followed by fever and rash, which can begin three to seven days after the first symptoms show.

Measles is relatively uncommon because of the widespread use of the vaccine, but can be brought into Australia from overseas travellers.

This case is one of several measles outbreaks in Victoria this year, including one linked to a British backpacker and another a flight between Denpasar, Sydney and Melbourne.

Locations visited by the newly diagnosed cases include: