Top doctors in Waikato and Northland are calling for a national immunisation programme against measles urgently.
Measles cases continue to climb in Auckland, with an extra eight announced yesterday alone taking the total for the region so far this year to 812.
On Auckland's southern border, the large Waikato District Health Board has had seven new confirmed cases of measles in the past two weeks.
Its medical officer of health, Richard Hoskins, said that had put all health authorities in Waikato - from health centres to hospitals - on high alert.
"We know at least six of the seven confirmed cases we've got here are of the outbreak strains which are circulating in Auckland and ... for one of those basically it was an Aucklander who had been living here at the time and had definitely been exposed in Auckland."
Dr Hoskins said such spread of measles was inevitable given major gaps in immunity against measles in Waikato, notably among those aged 14 to 37, many of whom had not had the MMR vaccine.
He said one in five people in that age group were not immune to measles, and an immunisation programme was needed to change that.
"So I would start in Auckland if I couldn't do it everywhere at the same time. And then I would roll it out, as able, across the country starting with the big urban centres and finishing off with the smaller DHBs [district health boards]."
The Health Ministry said on Monday it was considering a national immunisation campaign, among a range of options, to protect those aged 15 to 29 and others.
It could not give a time frame for a decision, but Dr Hoskins said action was needed before now. "Well we wouldn't be in the situation now in Auckland if it had been taken six months ago, or two years ago."
Meanwhile north of Auckland, Northland also has lower immunity. The region's medical officer of health, Catherine Jackson, said they needed to do more but it was an uphill struggle.
"Most teenagers and adults don't have immunisation records," she said. "They've been lost as they've grown up. They've moved general practice so they don't know. So that's a really difficult population to reach because they think they're immunised and they think they're immune but our testing suggests that one in five aren't."
As in Waikato, measles cases in Northland are coming from Auckland.
Dr Jackson said New Zealand - with a population of less than five million - had almost as many cases of measles this year as the United States, which has a population of more than 327 million.
"I think it's time to do something. We sit on the edge of doing something every outbreak where we kind of get very close to going 'okay let's push play on this' and we never quite get there."
Wellington GP Richard Medlicott said nurses at his Island Bay practice were run off their feet answering questions from patients anxious to find out if they had the jab.
"I know that in our practice we usually take about 80 calls a day. Yesterday it was 140 calls and maybe half of those were related to measles issues, either wanting to know if they'd been vaccinated or if they need to be vaccinated."
Drug-buyer Pharmac said New Zealand was using 20,000 doses of vaccine a month.
It said 10,000 extra doses had just been sent to Auckland, and it had enough stock for several months and was working to get more to meet ongoing demand.
- If you are showing symptoms, call a doctor but stay at home - do not visit the GP as you could spread the disease at the waiting room
- Measles symptoms include a fever, runny nose, sore red eyes and cough, followed a few days later by a rash usually starting on the face before moving down the body
- You can have measles and spread it to other people before you start to show any symptoms or feel sick
- It can take about two weeks to be fully immune after being vaccinated
- Healthline offers free advice and has a translator service 0800 611 116
- Measles has a 90 percent infection rate, meaning nine out of 10 non-immue people who come into contact with an infectious person contract the disease
- Measles is a serious disease, and can lead to complications including pneumonia and in rarer cases brain damage or even death
- Read this explainer from March for more information