An urgent warning has been issued after another confirmed case of measles in Sydney, with fears of heightened risks for travellers as school holidays come to a close.

Six new exposure sites have been identified by NSW Health including Sydney Airport and two Sydney Train lines.

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The person is believed to have caught the disease during a holiday in South-East Asia, where there are a number of outbreaks of the highly contagious disease.

However they were showing no symptoms when they flew back into Sydney from Singapore on Sunday, travelled by train from the airport to Central and then on to St Leonards, and visited a coffee shop and Woolworths at Crows Nest.

The new list of exposure sites on Sunday, April 12, are:

• Woolworths, Crows Nest, between 3pm-4pm.
• Only Coffee Project, Crows News, between 2.30pm-2.45pm.
• Sydney Trains T1 Northern line — Central to St Leonards, departing Central between 7.15am-7.30am.
• Sydney Trains T8 Airport line — International Airport to Central, arriving at Central between 7.15am-7.30am.
• Sydney International Airport — Arrivals Terminal and baggage claims area, between 6.15am-7.15am.
• Singapore Airlines Flight SQ221 — Singapore Changi to Sydney International Airport, arriving at 6.15am.

Officials say the sites do not pose an ongoing risk, but anyone who visited them around the exposure times should monitor for symptoms for up to 18 days.

Northern Sydney Local Health District Public Health Unit director Dr Michael Staff said anyone who develops symptoms — especially those who visited exposure sites — should seek medical care and call ahead before arriving.

“Symptoms to watch out for include fever, sore eyes, runny nose and a cough, usually followed three or four days later by a red, blotchy rash that spreads from the head and face to the rest of the body,” Selvey said.

“Anyone with early symptoms who gets a rash a few days later should also think about measles, even if they haven’t attended one of the identified locations, and seek testing.”

Measles is highly contagious and spreads through the air when an infectious person coughs or sneezes.

People who are pregnant, immunocompromised or have an infant exposed within the past six days are urged to contact their local Public Health Unit.

The Health Department have also urged Australians to stay up to date with their vaccinations.

“Measles vaccine can prevent the disease even after exposure, if given early enough,” Staff said.

“Anyone born after 1965 needs to ensure they have had two doses of measles vaccine.

“This is especially important before overseas travel, as measles outbreaks are occurring in several regions of the world at the moment.”