The alert level system should be changed to reflect the risks of indoor gatherings and the need for widespread mask use, a public health expert says.
Auckland is currently at alert level 2.5 while the rest of the country is at level 2. Masks have become compulsory on all forms of public transport for anyone over the age of 12.
Cabinet Ministers will meet today to review the country's alert levels, which are set to expire this Sunday.
Some public health experts say the hastily improvised alert level system introduced at the start of the Covid-19 pandemic needs to be updated to eliminate the virus a second time.
Among them is the University of Otago's professor of public health Nick Wilson who told Morning Report that Covid-19 transmission at outdoor settings is rare, with a recent Japanese study estimating the risk is 20 times greater at indoor venues.
"So that highlights the need to focus on these indoor environments where people are close together and that's where mask use is critical," Wilson said.
For outdoor areas people might not need to wear masks or even worry much about social distancing.
"The science is suggesting it's these indoor environments, especially where people are talking loudly or singing, they're the ones we really need to focus on."
He believed Auckland would need a week of zero cases before it could move to alert level 1.
If the country moved to alert level 1.5 the economy could be freed up, as long as there was focused mask use and size limits of 50 to 100 people at any indoor locations such as bars, restaurants and gyms.
Size restrictions could be relaxed as long as mask use was stringent, however, one drawback was the country's lack of good digital technology support for manual contact tracing, he said.
The alert level system had been useful, but it hadn't kept pace with the science.
"It will be a bit more complicated but it will give people more freedom, for example, in outdoor places and it will speed the process to elimination."
The country can get back to elimination strategy via use of alert level 1 through to 2.5, widespread use of masks and genetic epidemiology looking at a virus genome which allowed a more specific understanding of outbreak.
"We've got better tools, China has succeeded with elimination, Taiwan has, five Australian states. This is a very infectious virus ... that's why we need to use these tools such as masks and we need to advance on the digital technology for improving on contact tracing."
There will be a few more weeks of restrictions but if the country made good use of technologies we could return to level 1 and the economy could be completely opened up, Wilson said.