Passengers on a Samoa to Auckland flight have been advised to watch out for the symptoms of measles after a traveller was found to have been carrying the infectious disease.
Auckland Regional Public Health Service (ARPHS) advised anyone on Air New Zealand flight NZ997 on August 19 to be extra vigilant, especially if they were not vaccinated.
The infected person did not know they had measles at the time.
Public Health Medicine Specialist Dr Maria Poynter said symptoms could take between seven to 14 days to show.
" ... you are most at risk if you're not immune to measles, either because you haven't been vaccinated or you haven't had the disease previously," Poynter said.
The flight landed at Auckland International Airport at 1.23am on August 20, and the infected passenger went into isolation shortly after arriving back in New Zealand.
Dr Poynter said symptoms to look out for include a high fever, runny nose, cough and sore red eyes.
"A few days later a rash starts on the face and neck, then spreads to the rest of the body."
Anyone on the flight who is unsure if they are immune to measles should talk to their doctor or call Healthline on 0800 611 116 for advice.
Anyone who starts developing symptoms should contact their doctor and be call ahead to prevent potentially infecting others in a waiting room.
The warning comes as all travellers to Auckland were advised they should be vaccinated for measles at least two weeks before arriving.
It follows a recent spike in cases across the country, with at least 773 confirmed cases - 700 in Auckland - so far this year.
For more information or advice on measles, call Healthline on 0800 611 116, or see the Auckland Regional Public Health Service measles page or Ministry of Health website.