A border worker who tested positive for Covid-19 "falsely stated" he had been undergoing testing, report finds.
The spread of Covid-19 through the Grand Millennium and Grand Mercure managed isolation facilities in Auckland earlier this year were likely due to aerosol transmission.
Three workers at the Grand Millennium tested positive for Covid-19 in March and April, and there were two separate incidents at the Grand Mercure, including two positive cases who were genomically linked.
One of the workers who tested positive had lied to his employer about being tested for Covid-19, health officials said.
Improvements have since been introduced to ensure the accuracy of a managed isolation and quarantine (MIQ) employees test and vaccination status.
Reports into the in-facility transmission were released by Director-General of Health Dr Ashley Bloomfield and joint head of managed isolation and quarantine Brigadier Jim Bliss on Thursday.
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Three workers at the Grand Millennium Auckland tested positive for Covid-19 in March and April.
While it was not possible to conclude with absolute certainty where and how transmission occurred in the facilities, the reports concluded aerosol transmission was the most plausible pathway.
Grand Millennium cases
Three workers at the Grand Millennium tested positive for Covid-19 in March and April.
Among them was a security worker, who was later found not to have been tested for six months, despite a requirement for staff to be surveillance tested every 14 days.
An internal review undertaken by MIQ and the Ministry of Health found the overall response to the three positive cases was strong.
While it was not possible to conclude with certainty what had happened, it found case A (a cleaner) and the index case were most likely linked via aerosol transmission in a hallway.
Transmission between case B and case C was likely by direct exposure from two workers on the same shift.
Business consultancy KPMG was commissioned to review how the security worker, employed by First Security, was not tested for months.
It found the security guard (case B) provided inaccurate information to First Security, stating they had undergone each of their required tests.
Case B said they had undergone nine tests between December 11, 2020, and March 24.
First Security was only made aware of case Bs non-compliance on April 8.
Bliss said the worker falsely stated he had been undergoing Covid-19 testing.
A number of changes have been implemented since this incident, including making the Border Worker Testing Register mandatory from April 27.
MIQ has also moved significantly from a high-trust model to a model where employee, employer and MIQ now share a greater responsibility for ensuring compliance with the Required Testing Order.
The fluid workforce of 5000 people, from 300 employers, were on the register with their NHI (national health index) numbers and contact details, Bliss said.
A new team at MIQ cross-checked an employees testing status with their employer if there were concerns, Bliss said.
MIQ workers must also check in to the MIQ site they are working at.
We have reduced the number of entry points in our facilities, Bliss said.
Grand Mercure breach
The Grand Mercure case consisted of two separate incidents.
One involved two positive returnee cases who were genomically linked, strongly indicating transmission had occurred inside the facility.
The second involved a Covid-19-positive returnee who was able to take a bus ride to go for a walk while in isolation.
This resulted in 14 other returnees on the bus being deemed close contacts and having to remain in isolation for another 14 days. There was no community transmission linked to the breach.
Guests from at least two isolation hotels in central Auckland, The Rydges and the Grand Mercure, were being bussed to exercise pens when Stuff visited in January. (File photo)
The joint review was carried out to determine what, if any, further improvements could be made to the MIQ system to prevent cases occurring via ventilation.
While aerosol transmission via the fresh air supply cavity seemed unlikely, it was nonetheless the most plausible transmission pathway, it found.
The risk of downward airflow between rooms appeared to be unique to the Grand Mercure but the overall risk of transmission to returnees at the facility was deemed low.
The review also found a breach in protocols led to 14 people having to stay an additional 14 days.
A secondary cases blue wristband was not removed in error, meaning this returnee could go on a managed isolation walk when they should not have.
Head of MIQ Brigadier Jim Bliss welcomed the findings of the reports, and the recommendations made, on Thursday.
A number of improvements to how managed isolation walks are managed were recommended, many of which were immediately implemented when the incident arose.
In releasing the reports on Thursday, Bliss said a number of recommendations had been made, which he welcomed, and action was well under way.
This included emptying out the Grand Mercure and Grand Millennium, and completing full, on-site assessments of the ventilation at both.
Extensive reviews and remediation of ventilation systems across all managed isolation facilities is under way.
Bloomfield said returnees to New Zealand and the wider community could feel confident in the MIQ system.
The overall risks to returnees of contracting Covid-19 within MIQ and taking it into the community had been, and continued to be, assessed as very low, he said.
More than 140,000 people have been through MIQ since the pandemic began.
Bliss said they needed to consistently adapt to how they managed MIQ and would continue to review how MIQ operated.