A measles warning has been issued in Perth after a person was diagnosed with the illness.

The West Australian Health Department says the person visited several public areas in Perth and Northbridge between July 12 and 14, including Universal Store, Tony Roma’s, Mechanics’ Institute Bar and Polly Coffee Bar.

People should remain vigilant for the onset of measles symptoms for the next three weeks if they are not immune to the infection and visited those places during that period.