West Australians are being asked to watch out for symptoms after a measles case was confirmed in Perth's northern suburbs.
The person acquired the viral illness overseas before attending shopping centres in Morley, Kingsley, Greenwood and Dianella on January 7 and 8.
People without immunity who attended the shopping centres on those dates could be exposed to infection, the health department says.
Symptoms include fever, coughing, a runny nose and sore eyes, and about one-in-every-five sufferers will require hospital admission.
An adult is meanwhile recovering after becoming the first person in WA to contract invasive meningococcal disease this year.
The uncommon but life-threatening illness is caused by a bacterial infection and can progress rapidly.