The Auckland maintenance worker who tested positive for Covid-19 had a cough but still went to work in a managed isolation facility for two days before he was tested.
His cough was put down to a pre-existing condition, so he passed his daily health check for two straight days - the day the South Auckland cluster was detected, and the day after, when Auckland was sent back into alert level 3.
Director general of health Ashley Bloomfield said the man's cough was mild and had receded when the man was at work.
Asked why the man wasn't sent home with his cough, Managed Isolation and Quarantine Minister Megan Woods said the man had passed his health checks, which included a temperature check.
But when pressed, she said the daily health checks were always being looked at to see if they could be improved.
The man's case has been genome sequenced and it is not linked to the current South Auckland cluster.
That means it might be a new chain of transmission, and officials are now rushing to ring-fence the case through tracing and isolating close contacts.
But Bloomfield said the case appears to be contained as all his close contacts - at the household and at Rydges Hotel, his workplace - had so far tested negative.
This is not the first time the daily health checks have come under scrutiny.
The checks should have been more rigorous for the two sisters who were wrongly granted early leave and drove from Auckland to Wellington - where they subsequently tested positive for Covid-19.
Bloomfield has said one of the sisters had symptoms, which were put down to a pre-existing condition, but their daily health check had consisted of an "Are you okay?" question when it was meant to be a rigorous run-through of each symptom.
Had that happened, they may have been tested in Auckland and their application for early leave may never have been granted.
13 new cases in the community
The revelations come as Bloomfield announced today that there are 13 new Covid cases in the community.
Twelve are linked to the current cluster and one remains under investigation but is believed to be linked.
Ninety-eight people linked to the cluster, including 44 positive cases, have been moved into quarantine facility.
There are six people receiving hospital-level care. Two are in Auckland City Hospital on a ward, and four people are in Middlemore.
The total number of active cases in New Zealand is 90, of which 69 are from the recent cluster, one more is a case in the community, and 20 are imported cases in managed isolation and quarantine facilities.
Cluster on track to be NZ's biggest
Bloomfield said this cluster was on track to be the biggest New Zealand has had, and that was partly because it started outside of lockdown and the contact-tracing is more thorough and efficient than had happened for earlier clusters.
People had also caught Covid-19 since Auckland went into level 3, but they were infected within households.
The travel history of the current cluster includes:
• Pak n Save Supermarket, Apirana Avenue, in Glen Innes, Auckland. A confirmed case visited the supermarket a number of times between July 31 and August 8, sometimes for up to an hour.
• Mt Roskill Primary School. A confirmed case was there in the 24-hour period between 1.40pm on August 10 and 1.40pm on the August 11.
Bloomfield said people who were in those locations at those times were casual contacts and at very low risk of catching Covid-19. They should be aware of symptoms.
Isolation hotel worker tests positive
Earlier Bloomfield said genome sequencing has shown a positive case unconnected to the current cluster. The new case is a man who worked at the Rydges Hotel managed isolation facility.
The man was tested on August 13 as part of the mandatory testing regime for all workers at managed isolation and quarantine (MIQ) facilities.
He had a cough on August 11, but he passed his daily health checks for two days before the mandatory testing.
One of those days was the day after the current cluster had been notified, and the day that Auckland went back into alert level 3.
Bloomfield didn't know at this stage how the man might have caught Covid-19, but the chain of transmission at this stage to be contained.
The man's household and workplace contacts who have been tested have returned negative results.
He didn't have direct interaction with guests, and maintenance workers had appropriate personal protective equipment, Bloomfield said.
The maintenance worker might have caught the virus from human-to-human transmission, which is partly why all guests and staff at the Rydges Hotel are being tested.
Another possibility was environmental contamination.
"There are a number of casual contacts from a church service - 56 people have all had contact made except for two, and are in self-isolation and are being tested as well," Bloomfield said.
Woods, the Cabinet Minister in charge of managed isolation, said the maintenance worker's Covid infection is not related to any incidents or systems breakdowns.
"This case highlights how tricky and insidious this virus can be."
Asked why the man wasn't sent home with his cough for two days, Woods said he had passed his daily health check, but those processes were always being looked at with a view to improving them.
The genome sequencing of the man's case matches that of a returnee who flew in from the USA and stayed at Rydges at the end of July.
Woods said the maintenance worker was not in the room as the returnee, which has been confirmed by the card-entry data.
"We are not seeing any glaringly obvious points of connection," she said.
Swipe card access has also shown clues about the returnee's movements in the hotel, and Woods said that the returnee mostly stayed in her room.
She said the systems hadn't been in place to regularly test all MIQ staff, even though it was announced as Cabinet's instructions on June 23.
Those staff were now all being tested. Why it hadn't been put in place earlier was a question for the Ministry of Health, she said.
Testing had previously been voluntary, she said, and about 40 per cent of staff at Rydges had been tested prior to the outbreak.
Auckland cluster contacts tested once
Bloomfield said there were 1880 close contacts of the Auckland cluster, 1691 of whom have been contacted and are self-isolating.
They were not routinely tested twice because they were in isolation for 14 days even if they test negative.
The surface testing from Americold was still to be completed, but Bloomfield said people being infected from those surfaces had essentially been ruled out.
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Testing at the border
More than 18,000 tests were processed yesterday, Health Minister Chris Hipkins said, and most of those were turned around within 24 hours.
More than 100,000 tests had been completed since the cluster emerged a week ago.
More than 3485 port workers had been tested, and 2194 of more than 5000 workers from different organisations that had accessed the Auckland port had been tested.
More than 6000 workers at Tauranga Port were also being tested.
Hipkins said 2407 of 4774 of Auckland airport workers had been tested.
And 97 per cent of the managed isolation and quarantine (MIQ) facilities in Auckland have been tested, he said.
Hipkins said that some border-facing workers didn't want to be tested, but there was no reluctance anymore.
He said reluctance or hesitancy to be tested was only one of the factors why border-facing workers weren't being regularly tested.
Hipkins said he hoped to pass two Public Health Response order later this week, one around testing of aircrew, and one formalising the routine testing for border-facing staff going forward.
He was still working through how often higher-risk border-facing workers should be tested.
Yesterday the cluster grew by nine cases, while over 26,000 test results had been returned in the previous 24 hours.
Hipkins told the Herald yesterday that the outbreak appeared to have been detected before it had a chance to explode - not only in Auckland, but all over the country.
But that was before the news emerged of a positive case unconnected to the cluster.
The current alert settings - level 3 in Auckland and level 2 in the rest of the country - are in place until 11.59pm on August 26, but Cabinet will review the settings on Friday.