The case came to light when a man sought Covid-19 testing after developing a sore throat. Photo / AP
After weeks of Covid-19 restrictions Aucklanders are waking to new freedoms this morning under alert level 2.
And the Ministry of Health has revealed more details of what's believed to be the true first Covid-19 case in New Zealand.
The case came to light when a man sought Covid-19 testing after developing a sore throat. His weak positive result and serology test results indicated an old infection of the virus which dates back to February 21.
"This infection occurred in late February following exposure to an infected person from Italy," the Ministry of Health said.
"At the time the family member was visiting New Zealand, they became ill with symptoms consistent with Covid-19, and the wider household then also became ill."
The family did not get tested at the time as they did not meet the criteria of having defined symptoms combined with travel from or through China. "Italy had not at that point been identified as a country of concern. This meant the New Zealand household was not tested at the time.
"This would mean that the infected family member from Italy is effectively now the first case we are aware of in New Zealand, as they have reported having symptoms on arrival on February 21, a week before our first reported case on February 28," the ministry said.
Five other family members have been identified as historical probable cases of the virus.
"Consequently, the other household cases would represent the first locally acquired cases of Covid-19 in New Zealand, given the onset of symptoms from February 29 for the confirmed case."
The cases all originated in the Waikato region. The ministry said they are no risk to the public.
"As part of the investigation, close contacts of this man during his recent mild illness have been tested as a precaution and have returned negative tests.
"We have known that some people can return a positive PCR test long after they have recovered from the illness and are no longer infectious."
Epidemiologist Michael Baker said the case was the longest he'd heard of to show up in a test after the person had first fallen ill.
"The testing is very sensitive and you can get debris from the original infection, which contains RNA, which is enough to be detected months later," he said.
"This person was February, that's the longest I've heard of ... that's really pushing out that maximum duration."
New Zealand's first Covid-19 case was originally believed to have been a person who had travelled to Iran.
There were three new cases of Covid-19 yesterday.
They are new community cases, and are a family group linked to the September 11 chartered flight from Christchurch to Auckland for people leaving a managed isolation facility having completed their 14 day stay.
Also on the flight was the man who tested positive for Covid-19 at the weekend whose virus is thought to have had a rare three-week incubation period.
There were 86 people on the charter flight. All have been contacted and so far 63 have returned a negative test.
Another case from the man's earlier Delhi-Fiji flight has now been genomically sequenced, and the result is a close match. The case is still being investigated, but he is thought to have contracted Covid-19 before arriving in New Zealand.