New Zealand now has eight confirmed coronavirus cases, including the first in the South Island.

Ministry of Health director-general of health Dr Ashley Bloomfield announced the seventh and eighth cases at a press conference in Christchurch on Sunday.

The seventh confirmed case was an Australian man in his 60s who arrived in Wellington at 12.05am on Saturday on Air New Zealand flight NZ828 from Brisbane.

The man, Andre Reynaud, had been tested for Covid-19 in Australia but chose to fly to New Zealand before finding out he had tested positive here.

Bloomfield said the man was now symptom free, but remained in self-isolation with his partner and another relative. He was surprised and disappointed the man had travelled while waiting for test results.

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The eighth case was a woman in her 30s from Denmark who was travelling in New Zealand.

The woman arrived in Auckland via Doha on flight QR920 on March 10, and then flew to Christchurch on Jetstar flight JQ225, arriving at 8am the same day. Bloomfield said she then travelled to Queenstown with her family in a rental vehicle. She was unwell when she arrived in Queenstown, and was hospitalised there.

MONIQUE FORD / STUFF The Director General of Health Dr Ashley said New Zealand had good testing capacity, but doctors would only be testing people who had symptoms, not those who did not.

"She is recovering well and planning is underway for her discharge," Bloomfield said. The woman would recover in self-isolation, he said. Close contacts of both cases would be required to self-isolate.

From 1am on Monday, everyone arriving in New Zealand barring those from the Pacific Islands will be required to self-isolate for 14 days. Bloomfield said there would be more health staff at airports to talk to everyone who arrived, asking them about potential exposure and any possible symptoms and making sure they knew what their obligations were around self-isolation.

"A number of new studies are adding to what we're learning about Covid-19, including that people could be infectious in the early stages of infection," Bloomfield said. This meant it was especially important for people to self-isolate, especially if they felt unwell.

The Ministry had also changed its guidelines on what constituted close contact from within one metre for more than 15 minutes, to within two metres for more than 15 minutes.

Meanwhile, health authorities are waiting on test results from a suspected Covid-19 case on board the Golden Princess cruise ship in Akaroa, Canterbury. All up, three people are in quarantine on the ship. No-one on the ship was being allowed off until the results were known, Bloomfield said.

"We are looking at our planning and response should we need to respond to a positive case on that cruise ship."

There was a lot New Zealand could learn from cruise ships in Japan and the United States which had large numbers of people infected with Covid-19, Bloomfield said.

Canterbury District Health Board chief medical officer Dr Sue Nightingale said the health board had been planning since January on how to respond to the coronavirus outbreak.

DAVID WHITE/STUFF The Health Ministry would increase staff at airports so public health officials met everyone coming in.

The CDHB was working with the primary care sector, and Nighingale said there would be community-based testing stations set up, with the first one ready to go on Wednesday. Canterbury Health Laboratories was one of the few labs in the country able to test for Covid-19, and Nightingale said the CDHB wanted to ramp up its testing capacity by having extra staff working and getting another testing machine.

Bloomfield said testing was for people who had symptoms.

"We want to find cases of Covid-19. This is imperative for our ability to stop community spread. Yes, we will be testing more people. But we will be testing people who have symptoms. We will not be testing people who have no symptoms and who might be anxious or concerned.

"We have plenty of testing capacity in New Zealand, however we need to ensure that it is used to identify cases, and that we get those test results back quickly."

There would continue to be cases in New Zealand, Bloomfield said, however he stressed everyone had a role to play to help slow the spread so the health system could cope and support those who needed it.