It has happened again. This time, a diligent worker, having followed all the protocols given to him, had returned a positive result for COVID-19. The 26-year-old had been serving as a resident support officer in the Australian Open quarantine program in Melbourne, Victoria. Yet for all that, he still could not avoid contracting the virus. Not knowing so, he visited no less than 14 exposure sites, including various supermarkets and stores, before showing symptoms.

A discouraging pattern is emerging from Australia’s hotel quarantine system. In January, 2.5 million residents across the Greater Brisbane area in the state of Queensland faced a short, sharp lockdown after a hotel quarantine worker tested positive for the virus. “The cleaner did everything right,” claimed the Queensland Premier Annastacia Palaszczuk.

Western Australia followed suit, with its government imposing a five-day lockdown in the wake of a positive test for a hotel quarantine guard. Known as Case 903, the guard in question tested positive to the UK variant of the virus, seemingly from a returned overseas traveller. He had not interacted with the person in question, having been stationed two metres away from the room at the Four Points by Sheraton in Perth. Paul Armstrong, state director of communicable disease control, revealed that security guards at quarantine hotels were not required to don personal protective equipment except in cases when guests would arrive or when the room door would open.

To add a troubling ingredient to this, a returned traveller in Victoria’s hotel quarantine tested positive to the British variant of the coronavirus on February 3. The coronavirus detectives were wondering whether this might be connected to a family occupying another room. CCTV footage does not reveal members of the family, or the individual in question, leaving their rooms at the same time to engage such menial tasks as putting out laundry or collecting food. Interest has shifted to the possibility that the viral load in the family’s hotel room was of such a high order that particles found their way through the corridor once the door was opened. Those particles, left in a poorly ventilated space, provided rich opportunities for infection.

The novel coronavirus beast is proving versatile, confounding its combatants. It has caused a kerfuffle amongst authorities in the Australian state of Victoria, who are still keen to host an international tennis tournament at considerable risk. Questions are being asked about emissions, facilities and equipment. Cadres of health experts are worried.

The Victorian Premier Daniel Andrews acknowledged that the spread of the virus by means of aerosol transmission had to be taken seriously. The Australian Health Principal Committee had “been dealing with some of these issues. No doubt this will be a feature of the report that I will give to national cabinet tomorrow.”

The Emergency Services Minister Lisa Neville had to confess that yet another breach in the quarantine system had taken place, despite no deviation from set health protocols. A change of tack was required. She explained as much to radio station 3AW: “Things like in the health hotels, we use N95 masks when we’re moving infectious people, but we may need to do fitted masks, that could be one of the procedures that needs to change.”

Focus inevitably shifts to the nature of how staff involved in the quarantine procedures are protected. Epidemiologist Mary-Louise McLaws, an advisor to the World Health Organization, insists that staff involved in the quarantine system wear additional protection in the form of face shields. “With a highly infectious variant, we don’t yet know whether you are more likely to catch it through your eyes.”

Then comes the issue of the environment housing travellers coming into Australia. For McLaws, stellar, and regular ventilation, is crucial in any designated facility. In terms of airflow shifts, hotels were poor relative to hospitals. “The airflow change on a COVID ward in a hospital is 12 complete airflow changes per hour.” Hotels were “not designed like that and you have up to six complete airflow changes.”

The way the virus continues to leak through the quarantine barriers is getting some of the professionals hot under the collar. “Why does this keep happening?” asked irritated epidemiologist Mike Toole of the Burnet Institute. “The answer is that there is no national standard and a stubborn resistance to taking aerosol transmission seriously.” An aspect of neglect lay in avoiding the deceptive way such transmission was taking place. “We need a national standard drawn up by the Federal Government that all states and territories adhere to.”

Other suggestions are offered as to how such a standard could be reached. Toole advocates throwing vast “resources at this problem.” Greater care had to be paid to ventilation and Personal Protective Equipment. “It’s our only defence because we won’t reach population immunity from vaccination this year.”

Aerosol transmission is the subject of a recent, yet to be peer-reviewed study from Bristol in the UK. Healthy volunteers and hospitalised patients were recruited in the study to study aerosol emission, examining breathing, speaking and coughing. “Coughing,” it was found, “was associated with the highest aerosol emissions with a peak concentration at least 10 times greater the mean concentration generated from speaking or breathing.” Room ventilation, or the air exchange rate, was also a critical factor, with poorly ventilated spaces “posing a potential risk to those even not in close contact”.

Public health officials find themselves in a bind as to how best to contain those arriving from overseas. Victoria’s Deputy Chief Health Officer, Allen Cheng, resorts to the stop gap approach. An “engineering review” of the hotels had been undertaken. Airborne transmission was recognised, posing greater concern given the arrival of new coronavirus variants. The processes had to be tweaked and improved. Health bureaucrats and administrators find themselves defending a doomed, leaking system.