Up to 1.6 million people in NSW could be hit by the first Covid-19 wave, and up to 80,000 may need intensive care simultaneously, health department says

This article is more than 6 months old

This article is more than 6 months old

Up to 1.6 million people in New South Wales could be hit by the first wave of a statewide coronavirus outbreak with up to 80,000 people likely to require intensive care simultaneously.

Health workers in NSW have been told to prepare for 8,000 deaths from Covid-19 over the duration of the epidemic, and that the “first wave” of the virus could last for up to 22 weeks.

A presentation from the state’s health department to hospital staff emphasises that the figures are “possible scenarios” and that “there are many assumptions with still a lot of uncertainty”.

Health minister says Australia cannot predict how many will die from coronavirus Read more

The chief health officer, Dr Kerry Chant, says preparations are under way for 20% of the state’s eight million residents to catch Covid-19.

Chant expects every person who becomes ill will pass it on to 2.68 others on average – although this could be reduced through self-isolation, social distancing and handwashing.

“We’re anticipating 20% of the population in the first wave to be affected,” Chant told a NSW budget estimates hearing on Thursday.

She said forecasts showed 5% of residents affected by coronavirus – or up to 80,000 people – would require intensive care.

Assuming a 20% infection attack rate and a 1.2% case fatality rate, the state is preparing for 8,000 deaths, with a range of between 4,000 and 12,000.

Experts have said the death rate may be much lower than 1.2%, given not all infections have been identified, and have also warned against reading too much into modelling before an epidemic is over and all data has been collected. But in order to prepare, health departments need to perform some modelling, including taking into account worst-case scenarios.

“We are not at this stage in a position to put out particular figures because the modelling has been evolving all of the time,” the federal health minister, Greg Hunt, told reporters on Tuesday in a press conference with the deputy chief medical officer, Prof Paul Kelly.

But NSW Health is nonetheless preparing for a first wave of illness lasting between 12 and 22 weeks, compared to 6-10 weeks for normal seasonal flu. However, a longer duration is more ideal as it means emergency departments and doctor clinics will not be inundated all at once.

Between general practices, pharmacies and emergency departments, the state is expecting 272,000 presentations of people seeking health advice.

Assuming a 22-week duration for the first wave of illness, NSW Health is preparing for coronavirus patients requiring 30% to 45% of hospital bed capacity for six weeks, and a 10-week surge on intensive care unit beds putting them at between 115% and 330% capacity. This would be on top of baseline demands, but the impact could be reduced by cancelling surgery and raising the threshold for admission.

Patients will require between 145% and 300% of staffed ventilated bed capacity for up to nine weeks, the department predicts. Additional surge beds could come from using operating theatre staff and ventilators, the department told hospital staff.

Guardian Australia has contacted NSW Health for comment.

A professor of infectious disease and physician Prof Peter Collignon responded to the modelling by saying that it did not mean anyone knew what would happen or that the worst-case scenario would play out.

“Hopefully, these scenarios won’t happen, so we need to prepare in case it does, and looking at what’s happening in Europe it’s not unreasonable to,” he said.

However, he said evidence globally showed that countries such as South Korea and Taiwan that had acted early, as Australia, had done, demonstrated that the virus could be well contained and that people should take hope from that.

“People who will not be affected severely do need to worry because they’re not immune and all of them have parents and grandparents, so they need to do all they can to minimise the risk,” he said. “That means stay at home if you’re sick, don’t go out, wash your hands, and look after yourself. Because if you do you will decrease the risk to others.”

Do you know more? melissa.davey@theguardian.com