Passengers who landed in Auckland on a flight from Singapore may have been exposed to measles, says a medical officer of health.
The flight NZ281 arrived at midnight on Wednesday.
Auckland's Regional Public Health Service said a six-year-old boy on the plane had measles - and passengers seated in rows 34 to 49 could have been infected.
Medical Officer of Health Dr David Sinclair said measles was a serious illness that was easily transmitted to others, and it could be another five days before symptoms appear in passengers.
Dr Sinclair said the public health service was contacting people who had been exposed to the disease to check whether they were vaccinated or not.
Passengers on flight NZ281 on Wednesday night should call their doctor or Healthline.