As the number of cases in the Delta outbreak grows, an increasing number of cases are popping up in schools - especially around Auckland.
As the outbreak spreads around the country, and with all students now allowed back to school, the number of affected schools will continue to climb.
So far the approach taken at each school has been different - from full school closure to just some people being required to stay home.
Schools aren't making those calls on their own. They are being advised by public health officials based on a complicated set of factors including the case's movements, where classes were held and whether the infected person wore a mask while interacting with others.
Officials have also started using a different classification system in schools, depending on students' vaccination status.
In the past week or so at least seven schools have had to take action after a person from the school tested positive for the virus.
Yesterday Tahatai Coast primary school in Pāpāmoa announced there was a "strong likelihood" of a Covid-19 case among the school community, with the school closed today to give all staff and students time to get tested.
Auckland's Epsom Girls Grammar School also announced on Thursday that a student had tested positive - but the school had not closed, and families were being contacted directly if they needed "particular information".
Earlier this week Baradene College confirmed a teacher was infectious while teaching last Tuesday, Wednesday and Thursday.
Western Springs College also said a student had tested positive and was possibly infectious while at school on November 9 and 10. But the school was advised it could stay open - the only contacts being isolated and tested were the 16 students who were with the case at a party on Friday night.
Onehunga High School closed on November 15 and 16 after a student returned a positive result for the virus on Saturday, having been at school last Monday and Tuesday while infectious. The two-day closure would let the school contact all close or casual-plus contacts.
And King's College told parents on November 16 that a Year 13 student had tested positive and students and staff who were considered close contacts would be contacted by health officials. But the school was able to remain open and had undergone a deep clean.
Pakuranga Heights School also stayed closed this week after an infectious student was at the school from November 8 -12. Close contacts were being asked to isolate and get tested.
This afternoon Bay of Plenty's Te Puna School also advised a school parent had tested positive - their children had been at school this week but were asymptomatic so it was considered a low-risk scenario.
Ōtorohanga College, Arahoe Primary, Fruitvale School and Oratia School have all also had cases earlier this month.
In recent days officials have also been using a new classification system for schools which differentiates between vaccinated and unvaccinated students.
Students and staff who haven't had two doses of the vaccine are generally being treated as closer contacts than vaccinated students, meaning they have more stringent testing and isolation requirements.
That reflects the higher risk of them catching and spreading the virus.
Schools are now required to have vaccine registers in place, showing whether kids and staff are unvaccinated, have had one dose or are fully vaccinated. Students who have not provided their vaccination status must be treated as unvaccinated.
When people come into contact with a positive case while they are deemed infectious, some scenarios will see them categorised differently - as a close contact, casual contact or casual-plus contact - depending on their vaccine status.
The Herald understands the new system is taking a more pragmatic approach to minimise the amount of time students spend off school where possible - reflecting that school is a "high priority, low risk" activity.
The new system is being rolled out at schools as the number of Covid cases coming through the gates is set to grow.
For example, last week at Mt Albert Grammar some 130 students and staff required Covid testing after a student with the virus attended school in early November.
But a number of students who were not fully vaccinated also had to isolate for two weeks after being upgraded to "close contacts" under the new system.
A teacher at Auckland's Sacred Heart College also tested positive for Covid after teaching two classes while potentially infectious on November 5.
Only one student was considered a close contact of the teacher, however, because the other 30 students in his classes were already fully vaccinated - they were merely considered "casual-plus" contacts.
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