Warning after Perth measles diagnosis

West Australians have been warned of a measles threat after a Perth resident returned home from the Philippines and was diagnosed with the illness.

A measles warning has been issued in Western Australia after a passenger on a Singapore Airlines flight was diagnosed with the illness.

The Perth resident returned home from the Philippines on January 29 and the WA Health Department says people who have been inadvertently exposed may be at risk if they are not immune.

People should remain vigilant for the onset of measles symptoms until the end of the month if they were on the same flight or visited Coles at Raine Square in the Perth CBD on the morning of January 30.