Get all your news in one place.
100’s of premium titles.
One app.
Start reading
ABC News
ABC News
Health

Tasmania tops the list for new COVID-19 cases per capita — but is that really what's going on?

Many other states have had large, ongoing outbreaks earlier on in the pandemic than Tasmania. (ABC News: Maren Preuss)

If you have looked at Tasmania's COVID infection rate per capita, you would be forgiven for freaking out.

Tasmania's seven-day average of cases per 100 people is 0.30, the highest out of any state or territory.

It is double the national average (0.15) and more than double NSW (0.13).

Case numbers are rising across the country and, while Tasmania's statistics in comparison to other jurisdictions might sound alarming, there is an important factor contributing to the higher number in comparison with other states.

According to epidemiologist Catherine Bennett, there is another side to the story — Tasmanians are better at reporting their illness to the state government, and better at testing, in part due to Tasmanians having a late introduction to widespread community transmission.

"Tasmania was so successful at keeping the virus out, apart from some outbreaks, it was really the first wave where Tasmania experienced COVID," she said.

"In other states, we've seen the same thing — you probably get better testing numbers first up where people are quite worried about the virus.

"Particularly when you have reinfections now, it might be that even in Tasmania we'll see the numbers of those who report drop down a little," she said.

And while acknowledging that the current spike was cause for concern, especially when it came to current hospitalisations, the Tasmanian branch of the Australian Medical Association agrees — Tasmanians are good at reporting their illness.

"We've got very good reporting and testing going on at the moment, thanks to our state government, so we're seeing high numbers ironically per head of population than a lot of mainland states, but I think that's because we're better at testing and reporting," president John Saul said.

So what's a more accurate state of affairs in Tasmania?

Luckily, there are some more reliable measures that could help tell us how infection is moving through the community.

Dr Bennett said it was important to look at the whole picture, and the rate of hospitalisations combined with case numbers was one good indicator.

"Hospitalisations tell you a bit about the background picture as well. And when you do look at those per million, Tasmania is just about the national average (160) for hospitalisations per million people," she said.

"One hundred and seventy-three people per million is still low but at the same time that has moved up a bit. It was only a couple of weeks ago at 83."

But it is not a perfect metric either — states count hospitalisations differently.

In any case, Tasmania's picture of health does not differ too much from others.

Tasmania benefited from staying shut to most travellers until 90 per cent of the population was vaccinated. (ABC News: Maren Preuss)

"You're at that difficult point of knowing what [COVID subvariant] BA.4 and 5 have really already shown you what they can do in terms of pushing up infection rates or whether you've got a bit more to see," she said.

"If I can compare to WA, they've climbed up 20 per cent in the last week as well, which is the climb Tasmania has seen.

"Tasmania, like the rest of the states and territories, is seeing a rise in cases and it might be climbing a bit faster than some of the other states like Western Australia, so that's certainly something to watch, but I don't think the true infection rate in Tasmania is going to be that far ahead of other states," Dr Bennett said.

The R effective

Michael Lydeamore, a lecturer in infectious disease and modelling at Monash University, said a metric he liked better than case numbers was the effective reproduction number, which helps better compare numbers across jurisdictions.

"It's the average number of new infections generated by a single person," Dr Lydeamore said.

"So if I had COVID and I spread it to five other people and then perhaps you have COVID and you spread it to three other people, then the average number of secondary infections between us would be four," he said.

Tasmania's R number is 1.22, the second-highest of all jurisdictions, which means there are cases happening faster in Tasmania compared to everywhere else.

"So on average, someone with COVID in Tasmania is infecting more people than someone with COVID in Victoria for example," Dr Lydeamore said.

But, he acknowledged, the problem with that measurement was it relied on case numbers.

And when there are a number of different strains in the community, it starts to get messy again.

Each strain has a variable risk of reinfection.

When will Tasmania reach the peak of its current wave?

Last week, Premier Jeremy Rockliff said the peak would probably hit in August or September.

Acting state health commander Dale Webster said it was important to note circulation patterns of the virus differed state to state, even country to country.

"I use flu as an example: traditionally, Tasmania has been four weeks behind other states with flu, so it's likely there is a pattern here that we're on a slightly different cycle to other states.

"The other thing that I would emphasise is that our hospitalisation rates continue to be lower than other states, and I think that's down to the success of our vaccination program being so high, but secondly, our COVID@home program being able to deal with vulnerable people before they get to hospitalisation."

Australians aged over 30 years to be eligible for fourth COVID-19 vaccine dose.
Sign up to read this article
Read news from 100’s of titles, curated specifically for you.
Already a member? Sign in here
Related Stories
Top stories on inkl right now
One subscription that gives you access to news from hundreds of sites
Already a member? Sign in here
Our Picks
Fourteen days free
Download the app
One app. One membership.
100+ trusted global sources.