"Case numbers are always big on a Tuesday because it picks up on the weekend tests – that pattern has been there for months and that's why the moving average is so important."
With the moving average of Covid-19 cases being up by 1917, Baker says New Zealand could be in trouble.
"All the signs point towards a large wave of Covid-19 with an abrupt rise in cases, and it's very distinct."
Aotearoa should look to countries like Japan and Singapore for inspiration, he said.
"They are mask-wearing societies, and there is also a big focus on staying home when you are sick, not going in to work – those are lessons we have not absorbed at all.
"We need to act proactively rather than overwhelm the hospitals – so isolation periods, mask-wearing and things like that."
Auckland University Covid modeller David Welch today said there was a substantial rise in the seven-day rolling average of cases during the past week.
He said if a new wave was starting, it was likely to peak towards the end of next month.
Welch said the modelling he'd seen suggested there could be 20,000 cases a day by that point - and if he was involved with the Government he'd closely watch the numbers, with a view to raising alert level settings.
The Ministry of Health today reported a further 24 Covid-related deaths. Three people were in their 40s, five in their 70s, seven were in their 80s, and nine were aged over 90.
There are 493 people in hospital with the virus, including 11 in intensive care.
And the Omicron subvariant BA.2.75 has been detected in New Zealand for the first time.
The ministry says at this stage, there is no evidence BA.2.75 requires a shift in the public health settings already in place to manage other Omicron variants.
On Friday afternoon, analysis of whole genome sequencing confirmed two cases in New Zealand with BA.2.75. Before testing positive for Covid-19, both had recently travelled from India.
BA.2.75 is a recently identified second-generation subvariant of BA.2, the dominant variant now circulating in New Zealand. BA.2.75 has only been recently identified as distinct from BA.2, and evidence on its transmissibility, immune evasiveness and severity is still preliminary and emerging.
"We do know BA.2.75 has some characteristics that look like they may enhance its ability to evade immunity, similar to the BA.4 and BA.5 Omicron subvariants, and there is early evidence overseas that it may be slightly more transmissible that BA.2. There is no current evidence that it leads to more severe disease, although assessing the evidence is at a very early stage," the ministry said.
BA.2.75 is causing global concern because it is believed to have certain mutations that enable it to dodge antibodies - giving it the ability to infect people who have had Covid before, as well as those who are vaccinated.
There are 493 people in hospital with Covid, 11 of whom are in ICU. This is how cases are spread in hospitals around New Zealand: Northland: 8; Waitematā: 101; Counties Manukau: 34; Auckland: 53; Waikato: 53; Bay of Plenty: 29; Lakes: 9; Hawke's Bay: 16; MidCentral: 14; Whanganui: 7; Taranaki: 12; Tairawhiti: 2; Wairarapa: 7; Capital and Coast: 37; Hutt Valley: 6; Nelson Marlborough: 10; Canterbury: 59; South Canterbury: 7; West Coast: 1; Southern: 28.
The seven-day rolling average for hospitalisations is 436. This time last week it was 338.
There are now 50,698 active cases in New Zealand.
One Auckland school says it is going back to online learning this week because of Covid-19.
A note on the Carmel College website says it's made the call to revert to online learning from today to Friday as it is no longer able to staff classes.
Meanwhile, the ministry yesterday said there had been an increase of Covid-positive Waitematā inpatients - including an outbreak at a community site.
There was also evidence of visitors to North Shore Hospital passing Covid on to patients.
"The public is reminded to stay away from hospital if unwell and to respect hospital rules if they do visit, wear an approved mask at all times, practice good hand hygiene and cough/sneeze etiquette as well as maintain physical distancing of at least one metre."
Yesterday, 6498 community cases were announced.