Point Chevalier School principal Stephen Lethbridge said the decision was made to bring back compulsory mask-wearing in class for all year 4 to 6 students after noticing cases at the school and in the community were significantly increasing.
"We think it is prudent that we make sure we keep staff and kids as safe as possible," Lethbridge said.
"We've noticed that we've got significantly more cases around the school and community this week than we did last week and the week before and that's in line with growing cases across the Auckland region."
Lethbridge believed other schools had already taken or were in the process of taking a similar approach.
Schools knew their communities best, the Ministry of Education said in response to the schools' decision.
"[Schools] are therefore best placed to make decisions that prioritise the safety and wellbeing of their students, teachers and support staff."
The move comes as experts said there was an "urgent need for Covid-19 action plans for schools".
University of Otago Wellington's Dr Amanda Kvalsvig, professor Michael Baker, Dr Jennifer Summers, Dr Lucy Telfar Barnard, Dr Julie Bennett, Carmen Timu-Parata, professor Nick Wilson and Massey University's Dr Andrew Dickson made the call in a blog posted online today.
"At the onset of the Omicron outbreak in Aotearoa New Zealand in early 2022, the Government announced a policy for schools that was essentially a business-as-usual approach, advising that schools would stay open through the outbreak", they wrote.
"However, protections to prevent Covid-19 transmission were incomplete and there have been significant adverse consequences for school communities."
Data from the Ministry of Health shows that 42 per cent, or 238, of schools in Auckland had Covid-19 cases reported in the past seven days.
Across those schools, 3212 cases were reported in the past seven days: 2729 were students, 372 were teachers and 111 were other staff.
Nationwide, 801 schools reported notified Covid cases in the past seven days.
Lethbridge said the school was following guidance set out in a scope from the ministry to be able to set local decisions based on local conditions.
The school hasn't had to go back to online or remote learning services yet, but Lethbridge said an increasing number of teachers were also testing positive for the virus.
In their blog, the public health experts said the pandemic policy for schools needed to change to a whānau-centred approach that took in-school transmission seriously.
Children aged 5 to 11 had only been eligible for their first vaccine dose two weeks before term 1 began, key ventilation and monitoring equipment hadn't been delivered and child-sized respirator masks, such as KF94s, weren't widely available and younger children weren't required to mask up.
"Furthermore, the international evidence was clear that longer-term symptoms of Covid-19 infection in children were a real and rising concern and that Omicron was spreading in school settings."
As winter arrived, the country needed to urgently introduce a Covid-19 action plan for schools to support children's access to education, and to protect them, staff, and their families from the virus and other winter respiratory infections.
The experts listed seven areas for immediate action, including "routine, ideally mandated" mask use indoors, sustained high indoor air quality, planning for short circuit-breaker closures when cases reach defined thresholds, and supporting students and staff to stay home if they're symptomatic, close contacts or need to shield whānau during a major outbreak.
They also wanted higher Covid-19 vaccination coverage, with intensive health promotion from trusted community leaders to ensure families are well-informed, and to counter disinformation, greater accessibility of vaccines and urgent action to address the high inequities in vaccine coverage.
Just 24.9 per cent of 5 to 11s are double-dosed, falling to 11.8 per cent for tamariki Māori and 14.2 per cent for Pasifika children. Children aged under 16 aren't eligible to receive a booster shot.
The decision earlier this year to prioritise school attendance without also providing strong protections and transparent outbreak information had had a range of unintended consequences, the experts wrote.
This included significant educational disruption as well as exposure of students, staff, and their household members to both acute and longer-term risks of Covid-19, "including long Covid in children and adults, with concerning implications for their health now and in the future".
"Children with persisting symptoms from Omicron infection are already being seen in New Zealand."
Epidemiologist Professor Michael Baker praised schools for returning to compulsory mask use.
"I really applaud the efforts," he said.
Baker said it was easy to say that yes, masks should be compulsory in schools and said that the rule should extend from Year 1 and not just from Year 4.
He said schools were a key environment of transmission of the virus.
"Masks are the only way we have of stopping transmission of this virus between school students and taking them home to families."
Lethbridge said mask wearing at the school for Years 1 to 3 is encouraged.
"Even though masks were never mandated for Years 1 to 3, we'd always encourage mask use and some of our 5-year-olds wear masks exceptionally well," Lethbridge said.
Parents welcomed the decision and Lethbridge said he received multiple emails expressing support.
Daily Covid-19 case numbers appeared to be tracking up in Auckland and other parts of the country.
Over the past four weeks, Baker believed case numbers in Auckland had increased by as much as 75 per cent since the low point and said there was a resurgence of cases overseas.
"If we can't take opportunities to slow its spread than we are going to see case numbers go up, we'll see hospitalisations go up, and we'll see deaths go up," Baker said.
