None were displaying symptoms, but all will be forced to quarantine and be closely monitored by health authorities at a dedicated facility in Bullsbrook, 43km north of Perth, for a minimum of three weeks.
“They’re going to be put into the strongest quarantine arrangements you’ll find anywhere in the world,” Health Minister Mark Butler said on Friday.
Associate Professor Suman Majumdar,chief health officer of Covid and health emergencies at the Burnet Institute in Melbourne, said the pandemic’s legacy has meant greater public awareness of the importance of responding to and containing an infectious disease outbreak quickly.
“I think people generally understand the devastation that Covid caused, and that we want to prevent that from happening [in the future],” Majumdar said.
“Swift action containing an outbreak is the best way to do that. That’s been the recommendation from every independent agency.”
The MV Hondius outbreak brought back memories of the Ruby Princess cruise ship, which was the scene of a large Covid outbreak at the start of the pandemic.
It docked at the Overseas Passenger Terminal at Sydney’s Circular Quay with about 2700 passengers and crew onboard, some of whom had cold and influenza-like symptoms.
Despite compulsory 14-day self-isolation requirements being in place for all international arrivals, those onboard the Ruby Princess were allowed to disembark unchecked.
In the weeks that followed, more than 663 passengers and crew tested positive for Covid-19, with 28 passengers losing their lives.
Following a lengthy civil case, the Federal Court in 2023 found cruise operator Carnival Australia, which chartered the vessel, was negligent and misleading in its representations of the risks of contracting coronavirus while on board.
While the risk of widespread hantavirus transmission is significantly lower than that of Covid, Majumdar said the “swift and transparent action” from authorities to quarantine the affected Australians and New Zealander and to provide clear messaging, had a noticeable impact on how the outbreak was perceived by the Australian public.
“A good lesson from Covid is that communication needs to be very transparent and stating what’s known and what’s unknown, rather than being absolute [about everything],” he said.
“We don’t know the full implications of [how hantavirus has spread] so in Australia we’ve responded with quite rigorous protocols involving the isolation and quarantine of those contacts, which is very appropriate and a significant step forward.
“We’ve also got a new agency, the Australian Centre for Disease Control, and that’s absolutely critical to our responses, and it’s important that people recognise that is a new mechanism we’ve got in place.”
Authorities believe one of the patients was infected before boarding the ship in Argentina, where the Andes strain of the virus is endemic.
The virus, which is spread through the urine, saliva and droppings of rats and mice, can incubate for up to 40 days before symptoms appear.
University of the Sunshine Coast Associate Professor Erin Price said while there is a “heightened risk” of localised Andes virus outbreaks around the world in the coming weeks and months, Australia has an advantage.
“As we learned during Covid, Australia’s geographically isolated location means we are currently at very low risk of hantavirus outbreaks in our community,” Price said.
“We do not have the rodent species that would lead to Andes virus becoming endemic in Australia, so our only risk is through imported cases from travellers.”
University of NSW school of population health lecturer Dr Md Saiful Islam said the cluster highlighted the need for a “One Health” – or unified – approach to epidemiological emergencies.
“The rapid identification of the outbreak, confirmation of the virus, and implementation of infection prevention measures are all important steps that likely reduce the chance of further transmission,” Islam said.
“However, precautionary measures should continue throughout the incubation period, including isolation, monitoring for symptoms, and careful infection control practices among caregivers.
“As this virus strain is not present in Australia, preventing environmental contamination and ensuring appropriate biosecurity management of waste generated from potentially exposed individuals are also important components of the public health response.”
Majumdar said governments should continue to respond quickly to public health emergencies while also thinking ahead to future responses.
“We need some innovative thinking around pandemic preparedness,” he said.
“The broader lesson is not that the public should be alarmed, but that preparedness is an ongoing responsibility. We need to keep investing in the systems, people and partnerships that allow us to respond well before a threat escalates.
“It’s likely that the next big threat like that will be spread through the air, and one of the main areas that isn’t advancing fast enough is airborne preparedness, which would be interventions that can prevent transmission through the air in public places and settings.
“When the big health emergencies hit, people are generally primed to do something, but we need to ensure … that governments work together to build overarching trust [in the community].”
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