The partner of the third person in New Zealand to contract coronavirus most likely also had the disease, but subsequently recovered and is no longer showing symptoms.
Health Minister David Clark says that person will be tested for the virus.
That is despite Director-General of Health Ashley Bloomfield telling media just hours beforehand that the person would not be tested.
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A family member of the now-infected man had been in Iran and returned to New Zealand on a Qatar Airlines flight from Doha to Auckland on February 23, flight number QR0920.
That's a week before the Government imposed travel restrictions on Iran.
The Ministry of Health is in the process of contacting people on that flight.
In a press conference this afternoon, Bloomfield confirmed the infected man – who had not been in Iran with his partner – lives in Auckland and is in his 40s.
"This third case of Covid-19 is classified as what we suspect is a case of family transmission," he said.
This is the first case of person-to-person transmission inside New Zealand and Bloomfield does not expect this to be the last.
The other two people confirmed to have had the disease contracted it overseas.
Bloomfield confirmed that, although the Auckland man's three other family members had previously been unwell, none of them are showing Coronavirus symptoms.
Nevertheless, two schools – Auckland Grammar and Ormiston Junior College – have been notified about the positive test as there is a family member at each of those schools.
Those two students are at home, in self-isolation and Bloomfield confirmed that there was no risk to students or staff in either of the schools.
Both Bloomfield and Prime Minister Jacinda Ardern continue to call for calm as one National MP has called on people to panic buy.
National's Hamilton East MP David Bennett said people "should" be out there bulk buying.
His comments have drawn criticism from the Government.
Speaking in the House on behalf of Prime Minister Jacinda Ardern, Winston Peters called Bennett a "clown".
Ardern herself called for calm this morning.
"The most important thing people can do is if they are sick, stay home."
She said New Zealand has "significant capacity" for testing for Covid-19 and New Zealand's hospitals can cope with the outbreak.
"I have every faith in our system."
Bloomfield said the man, in his 40s, who has contracted the disease does not require hospital-level care and is in self-isolation with his family.
Although he said it was likely the Auckland man's partner did have coronavirus, that person had since recovered.
"The implication is that they had been infected with coronavirus ... and there has been transmission in the family."
Bloomfield initially said the man's partner would not be tested for the virus as they were not showing symptoms.
But, speaking to media this afternoon, Clark walked that back.
He said the man's partner has been offered, and accepted, coronavirus testing.
"It's highly likely because they are asymptomatic, they will test negative for the virus."
But he said this would "give people some comfort".
Bloomfield said the Ministry of Health confirmed the coronavirus case at 6pm on Wednesday night; Clark revealed the case on morning media today.
National's health spokesman Michael Woodhouse was critical of this.
"It took 12-15 hours for Ministry of Health to announce the second case of coronavirus, while the third positive case was blurted out by David Clark on Breakfast TV this morning completely lacking in detail and only causing more concern."
Seven people are under investigation for the virus, Bloomfield said.
At the moment the ministry can do 550 tests a day, but that will be upped to almost 1000 within the coming weeks.
There is no connection between the first coronavirus case – where the person in question had returned from Iran – and the third case, the Ministry of Health confirmed today.
Meanwhile, six people who were in quarantine in Whangaparāoa after being on the Diamond Princess Cruise ship have been released to go home.
None of them had coronavirus.
If you were on the flight
Anyone who was on the Doha to Auckland flight QR0920 and is concerned or would like information should contact the Healthline number 0800 358 5453. Interpreters are available.
In addition to public health staff proactively tracing close contacts on this flight via seat number, contact will be made with everyone on the flight to provide relevant information.
Close contacts are people who were in the same row of seats, the two rows in front and the two rows behind.
Healthline knows the seat numbers and will be able to advise anyone on the flight whether they are considered a close or casual contact.