A measles warning has been issued for Jetstar and Virgin passengers who were on three flights between Thailand, Sydney, Melbourne and Christchurch last week after one traveller was diagnosed with the highly contagious disease.

The traveller was infectious while on Jetstar flight JQ28 that left Phuket at 9.45pm on March 18, and arrived in Sydney at the T1 international terminal at 10.30am on March 19, NSW Health said.

The tell-tale blotchy rash of a case of measles. Credit:ninevms

The traveller left Sydney on flight JQ517 from the T2 domestic terminal at 2pm on March 19 and arrived at Melbourne Airport Terminal 4 at 3.35pm.

The traveller then departed Melbourne on Virgin Australia flight VA99 at 6.35pm, arriving at Christchurch Airport at 11.35pm.