A Mayor at the centre of a new Covid-19 case is calling for the Government to lock down the whole North Island as Delta seeps its way around the country.

Waipa Mayor Jim Mylchreest says trying to extend the current North Waikato border - which includes Hamilton and Raglan - will be "really challenging" given the number of roads snaking in and out of the area.

Director of Public Health Dr Caroline McElnay today announced 39 new cases of Covid-19; 30 are in Auckland but nine are in Waikato, including cases in both Kawhia and Karapiro.

"It would be really challenging trying to adjust the alert levels without doing the whole country or the whole island really.

"Once it gets into the Waikato, from a practical point of view and I'm certainly no expert, but you've simply just got to look at the geography and the number of roads radiating out from the Waikato it's not as easy as blocking off Auckland.

"So practically, I don't know if it's going to be possible, but we've got to try and contain it because there's still a lot of people out there that aren't vaccinated and we're still likely to overwhelm our health services."

He said it would be hard to see the North Waikato staying in lockdown for just five days given the number of cases was now at 18 - and spreading beyond the level 3 boundary.

"It's hard to see it finishing on Friday which was what everyone was hoping for."

He felt sorry for businesses who were hurting due to the level 3 and 4 lockdown restrictions and hoped that could be sorted at some stage.

"Oh, I think it's been an absolute struggle. I really feel for businesses that are relying on contact with the population.

"Hospitality and events-type businesses. Realistically it's catastrophic and we've just got to get over that level of restriction.

"It certainly, even at level 3, it's difficult for businesses that's for sure."

He said it was tragic to hear of another Covid death, a woman in Middlemore Hospital.

Having Delta in Waipa was "concerning, but not unexpected I suppose with cases in Hamilton".

"We're that close to Hamilton city and close to south Auckland from that perspective. This virus can certainly travel at a great rate of speed."

Mylchreest asked residents to "stay calm, get tested and get vaccinated".

"Covid-19 has reached our community. It shows just how determined the Delta variant is to spread far and wide. Our best defence is to get vaccinated, contact trace and get tested if you have any symptoms."

Ōtorohanga district Mayor Max Baxter told the Herald earlier today he was unsure how to contain a case in Kawhia given there was only one road in and limited stores for locals to get supplies.

Like Karapiro, Kawhia is currently outside the north Waikato level 3 boundary and Baxter said he was unsure if or where the town would be plunged into a higher alert level.

Kawhia township is south of Raglan Harbour, Ruapuke and Aotea Harbour, about 40km southwest of Hamilton.

The Ōtorohanga District is at the bottom of the Herald's Top Towns table for percentage of people fully vaccinated - at just 32.9 per cent of the eligible population.

Mylchreest said Waipa and particularly Cambridge were likely on the other end of the spectrum with a relatively high vaccination rate.

"We're pretty good, but it's not good enough until we've got 100 per cent as far as I see it," Mylchreest said.

"It's the only way that we're going to get any sense of normality back in our lives, for people to not only think of themselves but the community. It's critical really."

Meanwhile, Baxter expected the Ministry to set up additional testing sites in Kawhia.

"So I think there's going to be a bit more activity out there."

Baxter said a positive to come out of the Covid case could be that the Ōtorohanga district can shake its title of having the lowest vaccination rate in the country.

"Maybe this will encourage people to get vaccinated.

"In a report that I read, the day before yesterday, it ranked all the councils across the country in regards to both vaccinations... it's terrible that it takes a heightened awareness to inspire people to get vaccinated but that's the case," Baxter said.

"As they say, Delta is the virus of the unvaccinated."

Baxter said he understood the apprehension about having the vaccine but once they had a member of their whānau affected, they would change their tune.

"Trust me if one of their whānau or friends got seriously ill or died as a consequence I'm sure their views would be entirely different.

"It's not vaccines that takes people's liberties away, it's Delta that takes people's liberties away, it's Covid itself, in essence."