A new case of measles has been reported in Auckland and people who may have come into contact with the person are being asked to watch out for symptoms.
Before the diagnosis, the infected person visited Auckland Airport's international check-in area on the ground floor and the public pre-departure area on the first floor between 5.45pm and 6.45pm on Saturday, March 18, as well as Silverdale Pak'n Save between 7.30pm and 8pm.
On Sunday, March 19, the person visited Albany Pak'n Save between 11am and midday.
Medical Officer of Health Dr Michael Hale said members of the public who visited those locations at the relevant times and who were unsure of their immune status should call their doctors' practice to check.
People born before 1969, or who have had measles, or received two doses of the measles, mumps and rubella vaccine (MMR) after their first birthday, are considered immune.
New Zealand gives free MMR vaccinations to all children at 15 months and 4 years. Two doses of the MMR vaccine is at least 97 per cent effective in preventing measles.
Hale said measles was one of the most infectious diseases and the virus was easily spread from person to person through the air via sneezing, coughing or normal breathing.
"Just being in the same room as someone with measles could be enough to catch the infection," he said.
It usually took 10 to 14 days for someone who had caught measles to start showing symptoms. If anyone had been infected at the locations identified above, they may start to develop symptoms between March 28 to April 2.
Measles usually began with a high fever, runny nose, cough and sore red eyes, followed by a rash starting behind the ears and spreading to the body a few days later.
One in three people with measles would develop complications, such as ear infections, pneumonia, diarrhoea or, in rare cases, inflammation of the brain.
Hale said anyone who developed symptoms should keep away from work and public places and seek medical advice.
They should call their general practice first to allow for them to make arrangements to assess them safely.
"Please don't just turn up at the doctor's as you could infect people in the waiting room."
Usually about one in 10 people with measles are hospitalised but the rate of hospitalisation for recent measles outbreaks in Auckland is nearly double.
The Auckland Regional Public Health Service was trying to identify people who had been in contact with the infected person and placing those at risk of developing the disease, those who are not immune, in quarantine.