An aerosol-based medical device commonly used by asthma sufferers is suspected to have caused the coronavirus cluster at Melbourne’s Holiday Inn quarantine hotel which has been closed for deep cleaning.
Returned travellers who had been staying at the airport quarantine hotel are being moved after a guest who had finished her two-week stay there and a food and beverage worker tested positive for Covid on Tuesday.
The Victorian chief health officer, Brett Sutton, said the “working hypothesis” for the spread of Covid-19 in the hotel was a nebuliser, which was used by an infected resident on several days in early February.
“It vaporises medication or liquid into a fine mist and especially when it is used as medication and someone is infectious or later tests positive, that virus mist can be suspended in the air,” he said.
Sutton said these tiny particles can remain in the air for a few minutes and travel several metres.
“We think the exposures are related to that event … [The] virus was carried out into the corridor and exposed the authorised officer, the food and beverage service worker and also the other resident. That makes sense in terms of the geography and it makes sense in terms of the exposure time.”
The additional cases were announced by health minister Martin Foley on Tuesday night, bringing the locally acquired cases linked to the cluster to three.
Premier Daniel Andrews confirmed that the person who used the nebuliser had been taken to intensive care and was “essentially fighting for their life”.
The woman who tested positive on Tuesday is understood to have been staying in the room directly opposite. Sutton said the aerosolisation of the virus may mean everyone on that floor in that time period was exposed.
The medical devices were not meant to be brought into quarantine hotels, raising questions as to why the infected person was allowed to have their personal nebuliser with them.
Andrews urged the public not to blame him for the outbreak.
“Let’s not be critical of someone who is in intensive care. I’m sure they didn’t believe that they were doing the wrong thing. But we’re taking extra steps to make sure that those machines are not in the hotel, therefore they cannot be used,” he said.
“This was a personal machine, it travels with the person, and that’ll be I think linked to this underlying medical condition, whether it’s asthma or something like.”
The Victorian government will now move all travellers quarantining in the airport hotel, so a “deep clean to the highest of standards” can be carried out on all floors and rooms.
Andrews confirmed on Wednesday that until more was known about the situation Victoria would not be going ahead with the planned increase of international arrivals.
“The prime minister has been informed of that. We believe that it is appropriate to have a very low tolerance, or perhaps no tolerance for risk, particularly risks that you don’t quite understand,” he said.
Victoria’s corrections commissioner, Emma Cassar, said extra precautions were now being taken to ensure travellers were aware of the ban on nebulisers and those screening travellers’ baggage were aware what aerosol-generating medical devices look like.
“What we’ve done since then, is at the airport we are now asking people when they’re coming through … We’re expecting to have signage with diagrams of what a nebuliser looks like, what a C-pap [sleep apnea machine] looks like and what other aerosol-generating devices look like so that we can get ahead of this,” she said.
“We are also implementing as of today, a nurse who will accompany border force in baggage screening procedures so that we can actually detect these things coming through so that we can have a greater level of assurance.”