Auckland now has 94 confirmed cases of measles as the outbreak continues to spread, while 10 teenagers in Waikato have been exposed to the virus.
LATEST: Five infected people have required hospitalisation and eight others have been quarantined.
Most cases have occurred in west Auckland but it has spread to central Auckland, the North Shore and Manukau.
Patients treated in hospital include children too young for immunisation and people with cancer.
Medical health officer Dr Richard Hoskins said many other patients had visited emergency departments and had short stays.
"The latest rise to 94 confirmed cases has included several cases associated with the Ranui Baptist Church, where a number of un-immunised people have developed measles."
Hoskins said almost all of those recently infected had not been immunised.
He said immunisation protected the person receiving the vaccine and also stopped it spreading.
Hoskins said people who had not been immunised or had the disease before may be quarantined for 14 days after coming in contact with anyone infected with measles.
These people were required to stay at home and not go to school, work or any other public places until they could be certain they had not contracted the disease.
Symptoms of measles included fever, coughing, a blocked nose and sore red eyes.
Those who detected those symptoms in themselves or their children should phone their doctor before visiting as the disease was highly infectious and could spread through waiting rooms.
People could also call Healthline on 0800 611 116 for advice.
MEASLES OUTBREAK IN WAIKATO
Waipa schools in the Waikato were this morning put on high alert over a measles outbreak after 10 teenagers including some Te Awamutu College students were exposed to the virus.
Three of those teens were confirmed as having the illness, while seven were suspected of having it.
Waikato District Health Board was notified of the outbreak late last week, during the school holidays, and was working to prevent the highly infectious disease from spreading.
However Medical Officer of Health Dr Dell Hood said it was very likely the virus had already spread, and a worse case scenario was that hundreds of people could potentially be infected in the coming weeks.
"It's so infectious. We've got to try and interrupt an epidemic that is probably already reasonably well spread around by these first young people not realising what it was until it was probably too late.
"We're going to get some second and third generation cases quite likely, but what we're aiming to do is stop the further generations."
The DHB had sent a letter to all Waipa schools, which were beginning term three today, while the Education Ministry was contacting early childhood centres in the region to notify them of the outbreak and precautions that should be taken.
"People who are sick need to go home and if the next day they're better then they can go back," Hood said.
- JESSICA TASMAN-JONES/Auckland Now, with NATALIE AKOORIE/Waikato Times
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