New Zealand has hit a grim new high of 160 Covid-19 community cases as daily infection numbers are roughly doubling every two weeks, an expert says.
That raises questions about how Auckland's health system will cope in coming weeks, University of Otago epidemiologist Professor Michael Baker says.
Already contact tracing teams are straining to keep up with cases as the outbreak spreads to a West Auckland rest home and new infections pop up in Northland, Waikato and Christchurch.
Two unusual cases in Christchurch – including one who flew from the city to Tonga where they then tested positive for Covid-19 – have raised concern over whether the virus is spreading undetected.
In Auckland, one expert fears Covid-19 could be spreading among people who aren't coming forward to be tested, while yesterday up to 5000 people marched through the city to protest lockdowns and mandatory vaccination.
Auckland may now be only four to five weeks away from having 90 per cent of its eligible population fully vaccinated, allowing the city to break out of lockdown.
However, with 47 people in hospital, Baker fears daily Covid-19 cases and hospitalisations could climb much higher by that time.
"Vaccination coverage is rising, but it is unlikely to be rising fast enough to have a huge impact on the level of cases we see," he said.
That made it important to keep a close eye on how Auckland's health and contact tracing system coped, he said.
That will give clues to how the system will cope with increased numbers in the near future.
It will also will act as a gauge for how the Government's new traffic light system – which seeks to manage the virus' spread without using national lockdowns – might cope when it is rolled out across the country.
Yesterday's record 160 new community cases included 151 in Auckland, seven in Waikato and one each in Northland and Canterbury.
Of those, 95 are yet to be linked back to a person known to have Covid-19, while 35 have been linked to the outbreak.
The number of people hospitalised with the virus rose by 10, with 21 in Auckland hospital, 14 in Middlemore and 12 in Waitematā.
Two people are in intensive care. The average age of those hospitalised is 45.
Nine people have now tested positive for the virus at Edmonton Meadows retirement village in Henderson, West Auckland.
The eight additional cases include seven village residents and one staff member testing positive yesterday.
"It's important to note there are high levels of vaccination among residents of the home, and all staff are fully vaccinated," the Ministry of Health said.
All staff and residents would be further tested for Covid-19 on days 5 and 12, it said.
Of the five new Waikato cases, three were in Hamilton, one in the Te Awamutu-Kihikihi area, and one in Ōtorohanga.
Two Hamilton cases and the Te Awamutu/Kihikihi case have been linked back to the outbreak.
But health teams were yet to find a link for the remaining four cases.
In southern Kaipara, four infected people were from the same household, the Ministry of Health said. Only one of those cases was included in the day's official tally, with one reported the day prior and the remaining two to be in today's count.
In Christchurch, one person tested positive after recently returning to New Zealand and isolating in a hotel in Auckland.
They returned a negative test in MIQ and are fully vaccinated. Health teams are investigating whether their infection is a historical one.
Another person flew via Wellington from Christchurch to Tonga, where they tested positive, on October 27. They had received a negative result from a pre-departure test and are fully vaccinated.
University of Auckland Associate Professor Siouxsie Wiles said the unusual cases raised questions about where the person caught Covid - in Christchurch or overseas.
"The answer to that question has implications for Christchurch's alert level settings," she said.
University of Otago's Baker said the government will need to act quickly to put Christchurch into level 3 if it suspects unlinked cases are spreading in the city.
Case numbers have bounced around in the past week, with a previous record high of 129 cases on Friday, October 22 and 125 cases on Friday, October 29, while on other days new cases have dropped under 100.