New Zealanders are being given mixed messages about whether passengers should wear masks on public transport or not.
Auckland Transport says face masks are strongly advised while using public transport as an "added precaution against the spread of Covid-19".
However, the nation's top health official - director general of health Dr Ashley Bloomfield - and his team do not recommend face masks on public transport.
"At this point, we are not recommending people use face masks routinely," Bloomfield said.
"We don't think it is an important part of our overall measures.
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"The most important parts are the physical distancing and hygiene and other safety measures, and, of course, maintaining the bubbles."
Passenger numbers are expected to soar next week as more New Zealanders go back to work under alert level 3 and the city's bus timetable returns to normal after weeks of reduced services during the alert level 4 Covid-19 lockdown.
Bloomfield said debate over the effectiveness of masks remained divided.
"You can find very high-level specialists on both sides of the argument."
People not used to wearing masks might find it uncomfortable and be tempted to unconsciously use their hands to adjust them regularly, potentially bringing germs from surfaces they touched into contact with their faces.
If masks became wet on people's faces, viruses, such as Covid-19, could also transmit through them, he said.
Auckland buses and trains have been carrying about 85 per cent fewer passengers than normal during the Covid-19 lockdown - but operators say those travelling are important passengers like nurses.
Under alert level 3, any member of the public making an essential trip to school or work will now be allowed back on trains and buses.
During alert level 4, only those deemed "essential workers" could travel.
That led city trains and buses to carry an average 13,618 passengers per day over the past three weeks - dramatically down on usual passenger numbers.
NZTA is covering the cost of the free fares. It estimates that will total $19 million by the end of this month.
"Our public transport services are running at a reduced timetable, this equates to approximately 68 per cent of our normal service," an AT spokeswoman said.
"However, when you take into consideration the need for physical distancing, it looks more like 15 per cent of normal capacity."
It had been important to maintain a regular bus service during the lockdown, despite the greatly reduced passenger numbers, AT said.
Under alert level 4, Monday to Saturday services have been running on a timetable close to that normally used on Saturdays, while Sunday's timetable has remained as normal.
Importantly, this had greatly helped healthcare workers, the organisation said.
About 14 per cent of its passengers - or an average 2124 per day - travelled to or from hospitals.
Passenger numbers were expected to jump when bus services, including school buses returned to a "normal timetable" after Anzac Day.
School buses would also start up next Wednesday, April 29 - as April 28 was a teacher-only day.
"Our bus staff are in the process of contacting schools that are serviced by AT school runs," AT's spokeswoman said.
Schools were being asked when they expected to reopen and how many students were expected to attend.
"We appreciate that this will be a difficult question to answer, but a best estimate helps us plan," the spokeswoman said.
Under alert level 3, all bus services, including for schools, would remain free.
But passengers were requested to tag on and tag off with their HOP cards so AT could gather information about how many people were using the buses.
"Students without HOP cards can also travel free, if there is room on the bus, but we would prefer it if they purchased a HOP card so we can more accurately monitor how many people are on board," she said.
AT said it had improved its "cleaning regime to include antimicrobial protection fogging of facilities and our fleet".
Under alert level 3, travel on public transport is possible for the following reasons:
• Accessing local services and businesses.
• Going to work and school.
• Low-risk recreation in local area.
• Extended bubble arrangements.
• Travelling to permitted gatherings
Motorists should also expect roads to become busier.
Parking meters will remain switched off for the time being, so motorists can continue to park in AT buildings and on the street for free.
Under alert level 4, e-scooters and e-bikes are not available for hire. It is unclear if that will change under alert level 3.