Health authorities are still trying to reach passengers on three recent flights who may have been exposed to measles.
A person with measles, who would have been infectious at the time of travel, flew on domestic flights on Sunday, March 2 and Tuesday, March 4, the same day an infectious passenger arrived in Auckland on a Singapore Airlines flight.
The domestic flights were NZ501 from Auckland to Christchurch, departing 6.50am on March 2 and NZ548 from Christchurch to Auckland, departing 6.55pm on March 4, while the international flight was SQ285 from Singapore that arrived in Auckland on March 4.
The latest scares follow news that two passengers with measles travelled on an Air New Zealand flight, NZ136, from Brisbane to Auckland last month.
"We can confirm there was a person with measles - who was not a confirmed case at the time of flying, but who would have been infectious at the time of travel - on the two Air New Zealand [domestic] flights," Auckland Regional Public Health Service medical officer of health Dr Richard Hoskins said.
Health officials were still trying to contact passengers sitting within 10 rows of the infected person, but he said the passengers could have also travelled to other parts of New Zealand or overseas.
It can take 10-14 days for someone who has caught measles to start showing any symptoms.
Anyone on those flights who had caught measles from the infected passengers should be starting to feel unwell between today and next Tuesday - if they're not sick already - he said.
"Passengers who sat nearest these cases have the highest risk and are our first priority, and their local public health service will try to contact them if they might be susceptible," Hoskins said.
"However because measles is an infectious airborne disease, we want all passengers to be aware and vigilant."
There have been 69 confirmed cases of measles in Auckland so far this year, nine of which were acquired overseas.
Of these cases, 46 are from Westlake Boys High School.
A measles outbreak in 2011 led to 500 people being infected nationwide including many who needed hospital care.
Hoskins said passengers from the flights who felt unwell should phone their GP or call Healthline on 0800 611 116 for advice.