This article has been updated after a correction to a statement from the school.
A Canterbury high school is preparing for a positive result for coronavirus for one of its students.
The Ministry of Health is urgently tracing contacts a Kaiapoi High School student has had with others diagnosed with Covid-19.
"Health authorities have been working with the school and family," principal Bruce Kearney said.
Parents and caregivers were first emailed yesterday afternoon with "some bad news" from Kearney.
"We currently have a person awaiting Covid-19 test results and we are taking a precautionary approach to managing this," he wrote.
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Kearney confirmed to the Herald this morning that it was a student who was being tested for coronavirus.
"We are a strong community and we will get through this," he said.
Later in the afternoon, Kearney updated parents and caregivers to say they are "continuing to manage the situation as the person having tested positive for Covid-19".
But he later clarified they are moving forward "as if the student is positive" and that working closely with the Ministry of Education.
The Ministry of Health contacted Kaiapoi High, which has a roll of nearly 900 pupils, yesterday afternoon.
Ministry officials requested that all "staff and students need to go into isolation effective immediately" for the next two weeks.
It is more than the mandatory isolation that all New Zealanders will be experiencing from tomorrow – with self-isolation meaning that even in the home, people need to separate themselves from those they live with as much as possible and limit contact with people other than the people they're self-isolating with.
"I know that this is not the news that you will want to hear. This affects a large group of our community," Kearney says in his email seen by the Herald.
"My heart goes out to you all at this difficult time."
He asks people to follow Ministry of Health guidelines, especially as given that staff and students will all be in self-isolation, "there is little that the school can do".
"We will keep you up to date there is any changes to the circumstances. Staff will continue to make contact as per our pandemic plan," he adds. "I am sorry to have to share this with you all."
New Zealand now has 155 cases of confirmed and probable cases, with 40 new cases confirmed today, as the country moves into lockdown at 11.59pm tomorrow.