Health officials say there are now eight known cases of measles in the country – and the source of an outbreak was on a Cook Strait Ferry.
The latest outbreak follows one that started in Northland last month.
The outbreak on the Bluebridge Cook Strait ferry was on a Picton to Wellington sailing from 2pm-5.30pm on October 3.
Several of the current cases are connected to the ferry ride but health officials had been worried because they did not know who the original ferry case was.
They have now confirmed patient zero was from Northland.
Health NZ public health specialist Matthew Reid told RNZ they have been doing genetic testing and interviewing passengers.
Reid said there are a total of eight known cases in the country – in Auckland, Nelson, Northland, Manawatū, Wellington and Taranaki.
Health New Zealand is warning the sailing was a measles high risk exposure event with the potential for the disease to spread across New Zealand.
On Friday morning, Public Health medicine specialist Sharon Sime told Morning Report they were assuming the worst.
She said that anyone who was on that ferry and has measles symptoms, or even if they had measles symptoms which have now resolved, should contact Healthline or their health provider.
Bluebridge Ferry had assisted in providing passenger contact details to health officials to allow them to send out text messages and emails to passengers, she said.
But that did not include all passengers on that ferry as some people booked through other agents.
On Thursday, health officials named a Nelson cafe, public toilet and supermarket as locations where people may have been exposed to measles over a three-day period.
Get vaccinated before travelling
The Ministry of Health is asking travellers to get vaccinated before they go overseas after a spate of measles cases here.
Director of Public Health Corina Grey says there were active outbreaks in several countries that were popular for New Zealanders to travel to including Australia, Canada, the United States and India.
An overseas link of the current cases in New Zealand has not yet been established.
But previous outbreaks have been from non-immune travellers bringing the disease back with them from overseas, Grey said.
She said doses of the MMR vaccine prevented 99% of people from getting measles.
rnz.co.nz
