Victorian health authorities are investigating a case of COVID-19 in a hotel quarantine worker, with a public health team working to notify the staff member’s close contacts.
- The new case comes as authorities investigate the spread of coronavirus from one room to another in a quarantine hotel
- It is not yet clear if the new case is linked to the earlier reported spread of the UK strain of COVID-19 between rooms
- In the earlier cases, authorities said two groups of travellers on the same floor tested positive for the same variant of the virus
The new case was announced late on Wednesday night, and came after an earlier announcement, that authorities were investigating the spread of the virus from one room to another in a quarantine hotel.
It is not yet clear if the new hotel worker case is linked to the earlier reported spread of the UK strain of COVID-19 between rooms.
In the earlier cases, authorities said two groups of travellers on the same floor tested positive for the same UK variant of the virus.
A family of five and a woman in her 60s staying at the Park Royal Hotel returned genome testing results for the strain on different days.
The UK variant is not thought to be more deadly than other strains, but is understood to be dramatically more transmissible.
Emergency Services Minister Lisa Neville said the “working assumption” was that the viral load of one of the family groups was so high, the virus had travelled through the hotel just by the family opening the door to get food or drop off laundry.
She said one of the positive cases told authorities she remembered opening the door at the same time as someone else on the floor, which was being looked at as a possible source of transmission.
COVID-19 Quarantine Victoria (CQV) said the woman in her 60s arrived in Melbourne from Malaysia via Singapore on January 11, and previously tested negative on days three and 11 of her stay.
The woman’s husband, in his 70s, joined her in quarantine on January 16 and she decided to stay in the hotel with him for his 14-day quarantine period.
During that time, a family of five arrived in Melbourne from Nigeria on January 20, and were placed on the same floor.
The family tested positive on January 24, then the woman in the room opposite tested positive on January 28. Her partner has returned negative tests during his stay in the hotel.
Both the family and the woman were asymptomatic at the time they returned their positive tests. They have been moved to a health hotel for treatment.
Genomic sequencing late Tuesday revealed they had an “identical” strain of the virus, Ms Neville said.
At the time, she said the public health team looking at the cases had determined there was an “exceptionally low risk” of community transmission.
This afternoon, Ms Neville reported no staff had tested positive at that time.
There were 37 former occupants of the floor at the hotel who were isolating at home and being tested again in light of the news.
No breaches of infection control detected
Some 100 workers have been sent home and are being tested out of “an abundance of caution”, Ms Neville said.
CQV is investigating how the two cases are linked, including reviewing CCTV and undertaking environmental testing of the hotel, including ventilation systems.
Ms Neville said a review of CCTV showed there had been no breaches of infection control protocols on the floor of the hotel.
She said a ventilation report done when the hotel was first set up for hotel quarantine showed there was no shared ventilation, but the airflow was again being reviewed.
She said there was a fire escape located between the two rooms and health teams were making sure that it did not have an impact on the spread.
Deputy Chief Health Officer Melanie Van Twest said there was no indication at this stage that any staff or other returned travellers were involved.
“Certainly we’ve been unable to identify any breaches, anybody doing anything they ought not to have been doing, and we remain confident that our infection prevention and control measures are robust and adequate for the day-to-day circumstances,” she said.
But she said it may be a “perfect storm” or “a particular Swiss cheese line of holes, where everything has lined up to create this particular event”.
When asked whether the virus spread through aerosol transmission, Professor Van Twest said she was not “willing to put a name to it at the moment”, but that it was “clearly something that has hung around in the air”.
A dozen doctors wrote to the Queensland Government last month to warn that coronavirus spread at the Hotel Grand Chancellor in Brisbane was “most likely” airborne transmission.
Ms Neville said authorities would continue to try and house large families in family rooms, but there would be “buffers” between rooms occupied by bigger groups.