The number of measles cases across Auckland has now reached 1007, health authorities say.
That's up 37 cases in a day, Auckland Regional Public Health Service's medical officer of health Dr William Rainger said.
Nationally there have been 1214 confirmed cases of measles notified across New Zealand, according to the Ministry of Health.
Rainger said the increase in cases was slightly higher than previous days but not something to be concerned about.
"We look at the trend over time."
He classed the Auckland rates as a "serious outbreak". He would consider the measles outbreak an epidemic when there were "outbreaks across different geographical areas - it becomes a national issue".
Health authorities have previously said they expected the measles outbreak to peak soon. Rainger said there was still a steady trend upward but with high rates of vaccination in recent weeks, that could change.
The effects of the MMR vaccine took about two weeks to kick in, he said.
There had been a quadrupling of MMR vaccines being given out in the past three weeks. Some days there were 2000 doses being given per day, compared to 500 three weeks ago.
The Ministry of Health yesterday said it was asking GPs to prioritise the most needy in doling out their remaining MMR stocks, as the country awaits a new shipment of 52,000 doses.
Those are expected to arrive on the weekend and be distributed next week around New Zealand.
Rainger said Auckland's DHBs were working with public health organisations to regularly stocktake where vaccines were - and where they weren't - and redistribute them as appropriate.
"There's a huge supply chain challenge ... But the sector is rising to that challenge."
The sector's efforts to vaccinate were "much to be admired", he said.
They were being given two key priorities. The first was making sure young children were being vaccinated to schedule, as under-5s were most vulnerable to catching measles and to getting very sick.
Breaking the chain of transmission was the second key objective. 15-29-year-olds and Pacific people were a focus of vaccination efforts as they were the ones who had been disproportionately impacted by the outbreak.