Western Australians born in or after 1966 who haven't been fully vaccinated against measles can now get vaccinated for free.
Measles cases in WA have increased in recent years due to international travel.
There were 36 reported cases of measles in WA in 2018, the highest number since 2014.
There have already been 16 cases reported in 2019.
Those born prior to 1966 are usually immune to measles due to having the illness as a child.
Those 19 years old and younger are already eligible for the free vaccination through the National Immunisation Program.
Of all the infections in 2018, 73 per cent occurred among those aged 20 to 49 years of age.
If you are not sure if you have already had the two doses of measles vaccine, see your doctor, immunisation provider or travel health immunisation clinic for the free vaccination.
The state government program has been prioritised to respond to a growing number of reported measles cases.
Health Minister Roger Cook said measles was a serious and highly contagious viral illness spread by tiny droplets released when infected people coughed and sneezed.
"Complications from measles can be serious and in about 10 per cent of cases result in pneumonia," Mr Cook said.
"Prevention of measles is simple so I urge anyone who is not fully immunised against measles to take advantage of this free vaccination program, especially if you are planning a trip overseas.
"We want to stamp out measles and prevent future outbreaks of this serious disease in WA."
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