A FOURTH case of measles acquired overseas has been reported in a WA resident.
The cases are unrelated, but all four infected residents were diagnosed within a 10-day period in March.
Two travellers were infected in Bali, one in Malaysia and the other person was most likely infected in Thailand or Malaysia.
As a result of the infections, people could potentially have been exposed to measles at health care facilities including Bentley, Royal Perth and Joondalup Hospitals, GP surgeries and pharmacies, and other parts of Perth including Perth Airport.
Doctors are on alert for secondary measles cases that could present up until the middle of this month.
The spike prompted the Department of Health on March 24 to urge people to check and update their vaccinations prior to overseas travels from Perth.
It is recommended that the measles vaccine be considered for people travelling overseas who were born after 1965 and who do not have documentation of having had two doses of measles vaccine.
There may be an ongoing increased risk of measles infection in Bali.
One confirmed locally acquired case of mumps was also reported recently, with the source of the infection unknown.