A fresh measles alert for NSW has been issued after a man was diagnosed with the disease upon returning to Sydney from Southeast Asia.
The man spent time in Hornsby, Lane Cove, Lindfield, Sydney's CBD, Newtown and Erskineville while infectious between 30 June and 8 July.
NSW Health communicable diseases director Vicky Sheppeard said none of the locations visited by the man posed an ongoing risk but it can take up to 18 days for symptoms to appear following exposure.
"People in the same places at the same time as the man should be alert for signs and symptoms of measles until July 26," Dr Sheppeard said in a statement on Tuesday.
Measles symptoms include fever, sore eyes, a cough for three or four days followed by a red, spotty rash that spreads from the head down the body.
Two doses of the measles vaccine provide lifelong protection in 99 out of 100 people who are vaccinated, NSW Health said.
The vaccine is free for anyone born during or after 1966 who hasn't already had two doses.
"If you're unsure whether you've had two doses, it's safe to have another," Dr Sheppeard said.
More than 40 people have been diagnosed with measles in NSW since Christmas.
