Public health experts argue mandatory rules around mask-wearing will help counter New Zealanders' complacency about Covid-19.

Following the community case in Auckland last week, the government plans to make it compulsory to wear masks on public transport in the city, and all domestic flights.

Public health expert Michael Baker told Tim Beveridge mandatory mask use would be a visual reminder to people we're not out of the woods yet.

"If we look back over the last four months, we've had one border failure every two weeks over that period.

"It does remind us that we do want to avoid a repeat of that August situation in Auckland."

Baker says masks will also enable society to keep functioning, when there are small outbreaks like the one seen last week.

He says Taiwan made face masks mandatory even though they haven't had any cases for 200 days now as a way of preventing an outbreak. 

He says they are one of the limited tools that the public has to prevent themselves catching the virus. 

Baker says that the alert level system could use more nuance. 

"When we have a heightened concern as we've had in Auckland, rather than telling everyone they have to stay home as that's tough on businesses, we can say 'carry on, but let's use masks on public transport, and if the risk is higher, than schools, workplaces and meeting places'." 

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