Measles is back in New Zealand and travellers coming into the country are urged to make sure they have been immunised against the disease.
Every case of the highly contagious virus originated from people travelling into the country from overseas since 2012, the Ministry of Health said.
Nevertheless, a fourth case of measles has been confirmed in Canterbury around the same time one case has been confirmed in Auckland.
Auckland Regional Public Health Service said the person attended Clendon Medical Centre on February 19, 20 and 21.
The person appears to then have been moved on by the medical centre on February 21 because they were assessed at Middlemore Hospital around 5pm.
Medical officer of health Dr Jay Harrower said all patients at the medical centre or Middlemore around the same time might have been exposed.
"We will be contacting people who have been in the proximity of the case, but asking anyone who has been in these two locations on these days to be aware of the symptoms," he said.
"They should phone their doctor or call Healthline on 0800 611-116 for advice.
"If you feel unwell, please don't just turn up. It is important to call first, because measles is highly infectious and you could infect others in the waiting room."
The first symptoms of measles are a fever and a runny nose or a cough or red eyes before a red blotchy rash develops in the following days.
The rash usually starts in the face area before spreading to other parts of the body and can last for up to one week.
Ministry of Health director of public health Dr Caroline McElnay said children are those most at risk at contracting the disease.
In New Zealand, the immunisation is usually given to children aged 15 months then again at 4-years-old.
"It's important to stress the MMR vaccine is safe to give to children as young as 6 months," McElnay said.
"What's more, the MMR vaccination is free. Two doses of MMR vaccine gives long-lasting immunity, protecting at least 95 per cent of people."