Early learning centres are warning "mass closures" loom due to the lack of access to Rapid Antigen Tests (RATs). 

It comes after the Ministry of Education reported on Thursday at least 320 schools and early learning centres were fighting Covid-19 cases. That was double compared to the start of the week. 

Early Childhood Council chief executive officer Simon Laube said with these current rates and the lack of access to RATs it wouldn't take long before we're looking at mass closures. 

"Smaller centres only need one or two teachers to be positive and they'll have to close for long periods," he said. 

Laube said the impacts on children would be severe, citing a study released in January which showed education closures meant widening educational inequities, poorer mental health, behavioural difficulties, social isolation, family stress, family violence, and food insecurity. 

He said the council was disappointed with the lack of access to RATs and described the Government's current close contact exemption scheme as weak. 

"If more tests were available, regular 'Surveillance Testing' of all teachers and children would be more effective, but seems unlikely given limited supplies," Laube said. 

Early Childhood Council members were surveyed and 89.5 per cent hoped to use RATs to manage Omicron infection in centres, while 96.2 per cent believed it was the Government's responsibility to provide them. 

"New Zealanders' high vaccination rates have given the Government time to get this right and I hope they use it to expand testing using RATs," Laube said. 

The council urged the Government to redouble their efforts to source more RATs supply before the winter months arrived. 

"We believe better access to RATs will allow more centres to operate as children and parents look to get themselves through Omicron," Laube said. 

He was, however, impressed with the Ministry of Business, Employment and Innovation's scheme that allowed early learning centres to keep operating where they educate and care for the children of critical service workers. 

Primary schools were seeing a particularly rapid growth in case numbers from 76 on Monday to 196 on Thursday. 

Nationally, 50 early childhood services and 57 secondary schools were also managing cases on Thursday. 

Auckland Secondary Schools Principals' Association president Steven Hargreaves told RNZ on Thursday some schools were back to remote learning like last year. 

"It's right in amongst us. I know a couple of schools are closed completely and they've gone to remote learning." 

"We're all just clinging on, and we know that at some point we are going to lose a lot of staff and students home isolating and probably go back to remote learning like we did last year." 

He told RNZ the pool of relief teachers was small, with many choosing not to go into schools saying the risk of Covid-19 was too high. 

Hargreaves said they were in talks with the Minister of Education to be considered critical workers, and have access to RAT tests, so students and staff could get back into the classroom.