A lecturer in vaccinology says it's inevitable that more students and staff at Manurewa High School will be diagnosed with measles in an outbreak that she says is showing no sign of levelling off.
Thirteen students have so far contracted measles and the school has told anyone not immunised to stay home until Monday, and for those attending to bring proof of immunity.
Yesterday, the government updated the total number of cases of measles so far this year to 849, making it New Zealand's worst measles epidemic in at least 22 years.
The University of Auckland's senior lecturer in vaccinology, Dr Helen Petousis-Harris, expects more people to contract the disease at the school.
"It'll be inevitable because people are infectious before they develop any symptoms. So they could have been moving among other members of the school community and also outside that school community for some time before it was recognised that they had the measles," she said.
"We're talking about the most infectious disease that is known to man."
She said we can expect things to get worse before they get better.
"It looks to me like it's ramping up - the epidemic curve looks like it's heading into interstellar space at the moment. So there's no evidence that it's levelling off at this stage, which is really concerning."
Ms Petousis-Harris, told Morning Report there are pockets of really low vaccination coverage in the local community which is contributing to the spread of measles.
The reasons for this is a combination of things, she said, including older generations not being vaccinated, lack of access to healthcare and resistance to vaccinations.
Making it easier for people to access vaccinations is key, Ms Petousis-Harris said.
Just down the road from Manurewa High, Rowandale Primary School has also been rocked by the outbreak.
A teacher there was diagnosed with measles just over a week ago and school principal Karl Vasau said they're remaining vigilant for signs of the measles.
"We've got 610 children at Rowandale School and when this scare started and we started to make measures for children who aren't immune, we had about 170 children away on the day after that. We also had a large number of our staff away."
There's growing apprehension in the community, Ōtara-Papatoetoe local board chair Efeso Collins told Morning Report.
He said churches, marae and schools all need to be access points for people to receive key messages about the measles.
These messages need to be things like avoiding having people over for lunch after church, keeping people at home and away from children if they have symptoms, and get vaccinated.
"The fact of the matter is Pacific people, especially here in South Auckland, even if they've been told to stay home from school, which is causing the apprehension, they're still going to go to church, it's just part of our nature and we're not going to miss church."
He said families need to be encouraged to go to the GP, even if it means catching a bus or walking.
"A lot of our families live in poverty and we've got overcrowded houses, many of our Pacific people, 80 percent live in overcrowded houses, so you're going to have measles spread really easily and they're not going to know that.
"When you've got multiple families, multiple children in the house, if one person looks like they've got flu symptoms or measles symptoms you kind of focus on the rest of the kids and not the one who's presenting with those symptoms."
Transient issues in South Auckland mean people are missed by medical professionals, he said.
Auckland medical officials say the regional public health service is helping the school try to stop the spread of the virus.
Nationally, the Ministry of Health is boosting support for immunisation services tackling the measles outbreak.