The Government has no plans to stop unvaccinated children from attending school.
There are now 28 confirmed measles infections in the Canterbury outbreak and another 20 suspected cases, and two in Auckland.
Health Minister David Clark told The AM Show on Monday while the Canterbury and Auckland outbreaks don't appear to be connected, the southern city's strain of the virulent disease appears to have arrived from the Philippines.
We can't know for sure, but that's where we think it's probably come from. In Canterbury there's actually one case that's not connected to all the others - it's somebody we know was overseas and contracted it overseas."
Measles has killed nearly 200 people in the Philippines this year. The country's immunisation coverage has dropped from 80 percent in 2008 to below 70 percent now, according to the World Health Organisation, allowing the virus to spread and infect vulnerable people.
"The fear always is this becomes a widespread outbreak that's unable to be contained," said Dr Clark.
But he won't go as far as stopping unvaccinated children from attending school. Italy recently passed a law which allows parents who send unvaccinated children to school face fines of up to €500 ($825), and principals in Australia are allowed to send unvaccinated kids home in the event of an outbreak.
"I don't think it will be made compulsory to have children vaccinated," said Dr Clark.
"I don't think, for example, shutting them out of schools is a good idea. Children shouldn't be punished for the decisions of their parents - we want them to grow up to have a good education, to be able to make wise decisions for themselves.
"But we need to do everything we can to encourage people to get vaccinated. Some people could die. It is the case certainly in the Philippines with the outbreak there, that a couple of hundred people have died."
He says by going to school, unvaccinated kids will "get opportunities to understand the importance of being vaccinated" so they don't repeat their parents' mistake.
"This is an incredibly virulent disease - it's one of, if not the most, easily spread diseases. It highlights the importance of making sure people are vaccinated."
Thousands more vaccines will arrive next month so people who haven't had the two required injections can catch up.
"These things are prepared for. We are always vigilant. Knowing that we have over 90 percent of the population vaccinated is no reason for complacency - we actually need to do better."