"We are very aware there is anxiety in these types of things," he said.
"The advice we have been given from the Ministry of Health is that it is very low risk - you don't want to be too confident in these situations but we are happy with how we are progressing with this."
He said it did not appear that parents had taken students out of school today because of the school's link to the confirmed community case.
Fishing bosses have grounded a charter flight due to bring more international seamen into Christchurch.
The first intake of 240 crew members was due to leave a managed isolation facility today after dozens of them testing positive completed their stand-down.
This is on hold, however, as health officials have confirmed a worker has caught the virus where they are staying at the Sudima Christchurch Airport hotel.
A delay would stretch out the second flight chartered by Sealord, Independent Fisheries and Maruha Nichiro.
The companies signalled in September that unless border exemptions were made, seven deep sea trawlers would remain shore-bound - at a cost of tens of millions of dollars and many land-based jobs.
Sealord chief executive Doug Paulin said they hoped the Ministry of Health update at 1pm would signal when they could be cleared to leave.
He said there was no official timeline yet for the fishermen, or those on the next chartered flight.
Paulin said they want to ensure there was no risk to the community, even if it would mean a delay.
Once given the green light, the fishermen will be delivered by health officials to deep sea fishing vessels at Lyttelton.
The first vessel will head out to open water, but some of them will have to wait in another vessel until the second flight arrives and these crew members complete their managed isolation requirements.
At this stage additional sites have not been set up on top of the existing testing sites in the city.
Covid-19 community case may not go to isolation facility.
A person who has tested positive for Covid-19 may not be put into an isolation facility - which the Prime Minister says is "not unusual".
She confirmed work was ongoing around the community case, and said the person isolating at home was not an indication that the managed facilities in the Christchurch were at capacity.
The new case is a staff member working in the Christchurch managed isolation facility, understood to be the Sudima Hotel, where a group of international mariners have been staying.
The staffer had been tested on Thursday as part of ongoing screening and returned a negative result.
However they developed "mild" symptoms on Saturday and sought a second test on Sunday.
That second test was positive and authorities were alerted yesterday afternoon.
The person is now self isolating at home while decisions are made around their management.
This morning it was confirmed the person had one close household contact and had visited a supermarket - Countdown on Colombo Street in Sydenham.
Countdown's general manager corporate affairs, safety and sustainability, Kiri Hannifin, confirmed the person visited the store, but the time of the visit was not known.
Prime Minister Jacinda Ardern said a push alert would go out today alerting anyone who had been at the supermarket in and around the Covid-positive person.
She said it was completely normal for a person to start their isolation period in their own home and denied that they were there as a result of Christchurch facilities being full.
"Not at all - the case was only identified yesterday afternoon, it's not unusual for a bit of time to be taken to identify their close contacts, undertake testing that needs to be undertaken and then work through making sure we are putting the person in a facility if that's the right place for them to be," she said.
"It's not unusual."
A group of Russian and Ukrainian fishermen - many who had tested positive for Covid-19 - had been in managed isolation at the Sudima Hotel and were due to leave today.
A total of 31 positive Covid cases are now linked to the group of mariners.
They are among 440 fishers from Russia and the Ukraine, 270 of whom are due to go out on three Independent Fisheries boats next month.
Fishing company leaders have previously said they're happy to delay operations for the safety of the community.
They're paying for their isolation, flights and other costs.
Sealord expects to provide an update after the Ministry of Health's 1pm announcement.
The latest case in Christchurch ended 10 straight days of no community cases of the virus in New Zealand.
This is the third time Covid-19 has re-emerged in the community.
New Zealand went 102 days without a case until August when an Auckland cluster forced the city into a two-week level-3 lockdown.
Then in October, after 22 days without a new case in the community, a marine engineer tested positive after carrying out work on a ship in Auckland, the Sofrana Surville.
Four cases of Covid-19 were reported in managed isolation on Monday afternoon. One of those an international mariner staying at the Sudima in Christchurch, detected at day 15 testing as a close contact of a day 6 case.
The other three people were a person at an Auckland quarantine facility, who arrived on October 19 from Milan via Singapore and tested positive to routine testing at around day 12.
Another person arrived from London via Singapore on October 28 and tested positive to routine testing at around day 3. They are now in the Auckland quarantine facility.
And the forth case was detected in managed isolation in Auckland, after being given permission to join a family member recently arrived from overseas. The family member has previously been recorded in our positive case totals. Today's case will be recorded as an import-related case.
Last month Air Commodore Darryn Webb told Newstalk ZB staff at the Sudima Hotel took infection prevention measures including physical distancing, regular and thorough cleaning, PPE use, basic hygiene practices and daily health checks.
He expected the number of positive cases within the fishermen group to increase.
"I think it's logical to expect that. We knew in the planning that places like Russia are high risk."
Webb said the processes in place around testing at the border were robust.
"We have an exclusive use facility for these fishermen. Part of the process early on is that we do know they are coming from a high risk area so let's provide them a single location."
He said there was a 24-hour delay as the aircraft worked through its process in Moscow and the fishermen were assembled there for 48 hours and then en route for 18 hours.
That period of time provided an opportunity for the virus to spread.