Auckland's Albany Senior High School ordered shut as measles ...

Auckland Regional Public Health Service has ordered the school to close under the Health Act (file image). Photo: 123rf

Students and staff at an Auckland high school are being told to stay away while health authorities investigate a case of measles.

Te Whatu Ora says a student at Albany Senior High was infectious with the disease when they were at school last Thursday and Friday.

The school is a modern learning environment with five open-plan halls, and the student was in all halls while infectious, mixing with a number of year levels and classes.

All their household contacts are in quarantine and public health staff are now working to identify other close contacts.

Auckland Regional Public Health Service has ordered the school to close under the Health Act.

National Public Health Service's Dr William Grainger said many would be fully vaccinated but Te Whatu Ora wanted to check the immunity of all 100 staff and the 900 students.

"Public health is working as quickly as possible to check immunisation records, and will be in touch with students who are not immune to ask them to remain in quarantine and to provide them with further advice and support...

"In the meantime, we ask that staff and students who don't have two MMR vaccinations to stay home and not go to work, or social or sports events, or have visitors. The quarantine period for non-immune close contacts starts on Thursday (4 May) and they are required to stay away from others in case they are developing measles for a further seven days."

Auckland Regional Public Health Service was investigating the source of the infection.

The case had not been overseas recently, which meant they were infected by someone with measles within New Zealand, the service said.

The source of the student's infection was likely to be a person known to them who had recently travelled abroad, it said.

Measles is highly infectious.

The school was already closed for a teachers' only day tomorrow but will not re-open on Friday.

In a Facebook post, the school said: "This closure is in place while public health carries out contact tracing to check who else is at risk of catching measles. Please watch out for the letters that will be sent to parents, caregivers and staff. An update will be provided as the situation evolves".