Health authorities are warning parents of young children in Morley and surrounding suburbs to be alert to the risk of measles following a confirmed case in a baby who visited the Morley Library.

The WA Health Department said children and adults may have been exposed to measles if they visited the Morley Library on March 12 between 9.25am and 11am. This particularly relates to parents and children who attended the Rhyme Time or Story Time sessions.

People at the library during this time should be alert for the symptoms of measles until March 30.

The library is postponing the Rhyme Time and Story Time sessions until after March 30 to minimise the risk of further exposure.

People who are concerned they or their child may have measles should seek advice from Metropolitan Communicable Disease Control on 9222 8588 during office hours or call HealthDirect Australiaon 1800 022 222 after hours, and avoid going to public places.

Measles is a serious and highly contagious viral illness spread when infected people cough and sneeze.

Early symptoms include fever, cough, runny nose and sore eyes, followed by a red blotchy rash three or four days later.

Up to one-third of people infected with measles will experience a complication. This can include ear infections, pneumonia and encephalitis (swelling of the brain) which may require hospitalisation.

Parents are also urged to make sure their children receive their measles vaccinations on schedule. The measles vaccine is given to children at 12 and 18 months of age.

Older children and adults who have had two documented doses of the vaccine are considered immune to measles. People born before 1966 are also considered immune to measles because they have likely had the illness as a child