People who took a flight from Bali to Australia two weeks ago should watch for symptoms of measles after a fellow passenger was diagnosed with the illness on Sunday, the Department of Health and Human Services has warned.

Qantas flight QF44 from Denpasar arrived in Sydney at 6:25am on Saturday, March 10 and the passenger then boarded QF415, arriving at Tullamarine at 10:35am the same day.

Passengers on a flight from Bali to Australia have been warned to look out for symptoms of measles after a co-passenger was diagnosed on Sunday.

The man became unwell after the flight and was hospitalised on Sunday, following the confirmation of his illness. He may have been infectious during both these flights.

Public Health physician Dr Finn Romanes said they were working with airline officials to identify and contact passengers who shared both the international flight into Sydney and the domestic

flight into Melbourne.