A maintenance worker at the Rydges Hotel managed isolation facility has tested positive for Covid-19.

The man's partial genome sequencing results indicate his case is not linked to the community cluster.

The worker does not have any routine contact with guests, the Ministry of Health said in a statement before director general of health Ashley Bloomfield's usual 1pm press conference.

"The person returned a positive result for Covid-19 on Sunday, August 16, with symptom onset on August 11," the statement says.

"He was transferred to Jet Park Hotel quarantine facility on Monday, August 17. It has taken till this morning for genomic sequencing results to confirm the origin of the case."

Genome sequencing shows a returnee from the US with the same sequence as the maintenance worker stayed at the hotel from July 28 to July 31 before they returned a positive test on day three of their stay.

The traveller was moved immediately to the Jet Park quarantine facility on July 31 after the positive test.

There is no obvious person-to-person connection between the worker and the returnee from the US, however investigations are ongoing.

"Initial reviews of CCTV footage and swipe card movements so far show no interaction between the two people including no entry to physical locations occupied by the returnee from the USA," the ministry said.

"The room the USA returnee was in has been unoccupied since the case was transferred to the Jet Park quarantine facility and is still empty.

"The room underwent hospital-grade cleaning with hydrogen peroxide vapour sanitation using a BioQuell machine."

Contact tracing and testing has not connected any further cases to the maintenance worker.

To date, the maintenance worker remains a single case.

Six close contacts he worked with at the MIQ have been identified and are self-isolating.

All of the close contacts have returned negative results from surveillance testing last week, however, as a precaution all staff and returnees at the Rydges are being retested again.

"Forty-five staff members and 54 guests were tested yesterday, the remainder will be tested today," the ministry said.

"Three household close contacts of the man are all in self-isolation and have been tested."

The ministry also says the man attended two of the Emmanuel Cook Islands Good News Fellowship church services on the morning and evening of August 9.

Health officials have contact traced all attendees of the church as close contacts.

As of last night, all but nine of them had been tested and the remainder will be tested today. All are in self-isolation.

Deep cleaning of the school hall where the service is held is underway currently.

"Health officials are currently assessing if environmental testing at the Rydges would provide any further insight, however, the frequent deep cleansing of the facility means this is most likely not possible," the ministry said.

Meanwhile, another result has confirmed a separate case is connected to the Auckland August cluster.

Further genome sequencing and matching is being completed today and further analysis is expected later, the ministry said.

Actions undertaken at the Rydges Managed Isolation Facility

As soon as the positive test was established a series of actions were undertaken immediately at Rydges including:

• The hotel was put into immediate lock down on Sunday morning, as soon as the positive test was returned.
  • Thorough cleaning of shared areas of the hotel was carried out.
  • Close contacts of the staff member identified and put into self-isolation until tested (noting that this staff member was not in a public-facing role).
  • Lock down of guests in hotel lifted once cleaning completed and close contacts identified.
  • Close analysis of movements were undertaken at including: Review of CCTV, Review of room entry data to look for connection to cases.
  • Genomic Sequence sought from ESR.
  • Health advice sought.
  • Further testing of all returnees and staff undertaken.
  • Confirmation that infection prevention controls have been followed.
  • Normal procedures resumed.

The maintenance worker carried out tasks on vacant rooms between bookings, following full infection prevention and controls, including the use of PPE.

The ministry says all staff have been tested since the Auckland outbreak and as a precaution, they are all being retested.

Returnees are also undergoing testing and in some cases are being retested now.