Christchurch's Cathedral Square empty on Wednesday morning as New Zealand heads into another Covid-19 lockdown. Photo / Hamish Clark
South Islanders are being urged to take the Covid-19 lockdown down seriously as the Auckland case may only be "the tip of the iceberg".
Professor Michael Baker, of the University of Otago's public health department, said without a clear link between the community case and the border, the worst had to be assumed.
He admitted he was initially "surprised" by the decision to move the whole country into alert level 4 after a 58-year-old Devonport man tested positive for Covid-19.
However, that changed when more details emerged, including that the man had travelled to the Coromandel and had contact with people who may have then travelled to other parts of New Zealand.
It only took ''fleeting'' contact to be infected with the virus, he said.
"When you do not have a clear link to the border, what you are seeing may be the tip of the iceberg and you have to assume the worst."
Baker said the "critical" advice for people was if they had cold or flu symptoms, to contact healthline and get tested.
He hoped the situation would also be a chance for the Government to address two ''gaps'' in New Zealand's Covid-19 defence: making QR scanning mandatory for high-risk indoor environments and revising the alert level system, so it was more clear when masks were required.
After yesterday's announcement, supermarkets across the South Island were inundated with shoppers eager to stock up on supplies.
Student Joshua Gilchrist was among the crowd at New World Centre City, in Dunedin, after hearing the news.
"We are just getting the essentials to get us through the next few days; plenty of beer and snacks," he said.
Nancy Higgins, of Blueskin Bay, spent two and a half hours at New World last night.
"I'm not angry about it. It is something we have to do to keep everyone safe," she said.
In Central Otago, residents descended on Alexandra's sole supermarket — New World — en masse, causing traffic snarls on Centennial Ave.
Similar queues formed at bottle stores and service stations had bumper-to-bumper traffic.
There was congestion at supermarkets in Cromwell, despite announcements reassuring customers they would be open today.
The Southern District Health Board said a move to alert level 4 meant most scheduled surgeries and outpatient appointments would be postponed for three days and would be reassessed depending on alert level changes.
No visitors will be allowed in hospitals unless on compassionate grounds, but one parent may stay at the hospital if a child is being assessed, treated or is admitted.
The Dunedin City Council said it continued to prioritise the supply of critical services such as water and wastewater, and rubbish collection.
At alert level 4, council facilities, including libraries, museums, swimming pools, and sports and recreational facilities, must be closed.
It would appear unlikely the University of Otago graduation, due to be held on Saturday in Dunedin, will go ahead. More than 400 people are due to graduate in person across two ceremonies.