Australia’s COVID-19 performance: Good luck, good management or a combination of both?

Earlier this month the Morrison government released the Doherty Institute modelling that has informed its decisions to date. The modelling highlighted the potential for COVID-19 cases to rise rapidly across Australia in the absence of policy responses such as social distancing. Of course, Australia has enacted social distancing and progressively locked down the country, and, as a result, has seen a sharp ‘flattening of the curve’ in the number of positive cases of COVID-19.

Our economics team have examined global COVID-19 deaths, cases and resulting case fatality ratios (CFRs) to better understand the drivers of the variation, and the extent to which Australia’s relatively good performance is a result of good luck, good management, or a combination of both.

Global variation in COVID-19 cases, deaths and case fatality ratio (CFR), April 14th 2020

On first glance, it might seem surprising that the CFR varies so much across the globe. After all, death doesn’t usually discriminate.

Australia’s COVID-19 death rates are low by global standards. This is particularly impressive given our relatively elderly population, over 10 percent are aged 70 and above, and our strict testing regime to date, factors that tend to push up a country’s CFR. However, demographics are not the only driver: if Australia had the same demographics as Italy (16 percent share 70 and above), we could expect a CFR of around 3, whereas Italy’s CFR is almost 13. Interestingly, none of the comorbidity metrics we tested (e.g. smoking, obesity, CVD, chronic respiratory illness) explained any of the variation in CFRs.

One reason for Australia’s effective performance can be traced to our health system capability and preparedness, where we rank in the top 10 percent of all countries. Our analysis found this is strongly related to lower death rates.

Our health system’s capacity has held up to date, which is good news as our modelling shows, based on global analysis, that if cases reached a critical level relative to our health system capacity there would have been an associated increase in Australia’s CFR of 250 percent.

Australia’s efforts to successfully flatten the curve have also undoubtedly saved lives. Efforts to keep cases in check relative to our health system capacity is of critical importance to avoid a steep increase in the number of fatalities.

At the time of publication, Australia sat at less than 7,000 cases and 74 deaths; had that number reached 20,000 cases, we could have expected a fourfold increase in the number of deaths. While analyses tend to focus on ratios such as deaths to cases, our result highlights that the absolute size of the problem also matters: countries with relatively large populations, including Australia, are particularly susceptible to high death rates should case numbers creep up relative to health system capacity.

Australia’s testing regime to date has focused on testing those at high risk of COVID-19 infection, rather than testing of the broader population. Globally, this narrower type of regime is associated with higher death rates, so as more testing becomes available, we could expect our case fatality ratio to fall further.

The epidemiology of COVID-19, and global responses to it, are incredibly complex. The analysis presented here considered only broad, country-level factors based on available high-level data. The results should therefore be considered indicative only.

Additional authors: Dr Ashley Crouch, and Michael Cowling

Read the full analysis


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