West Australians are being urged to be alert to an increased risk of measles after four cases were reported in the past week.
That brings the total number of confirmed measles cases in Perth in the past month to nine, including four infants too young for vaccination.
Two of the nine cases were infected in WA.
One was in a hospital emergency department, where one of the patients infected overseas had attended, and the other was in the Kalamunda area.
The Department of Health said the patient in that case had no travel history and no identifiable source of infection, suggesting there had been an undiagnosed case in the area, so other people might have also been infected.
