With the recent surge in Covid-19, here is a progress report without the hype from the media, and without the commentary from those who doubt the impact of the disease.
I am attempting to show how Covid-19 compares with other major diseases in one important aspect: mortality. How deadly is it?
I use data from the Australian Bureau of Statistics reports Provisional Mortality Statistics, Australia, Jan 2020 – Oct 2021 and Covid-19 Mortality, released 22 December 2021, and Our World in Data.
To be certified as a Covid-19 fatality, Covid-19 must be the underlying cause of death- not dying of another condition while being positive for Covid. According to Covid-19 Mortality, 71.2% of people dying from Covid had pre-existing chronic conditions. The overall Case Fatality Rate (CFR) for Australia for COVID-19 as of 31 October 2021 was 1.0%, but while the CFR for those aged under 60 years was 0.1%, the CFR for males aged 90 years and over was close to 50%. 83% of people who died of Covid were over 70. It is therefore a relatively mild disease for younger people, but very severe for elderly and sick Australians.
I shall now tease out mortality statistics to show Covid in context.
Figure 1 shows weekly death tallies of deaths in which doctors certified Covid as being the underlying cause of death, and from November weekly death tallies from Our World in Data.
Figure 1: Weekly Covid Deaths from January 2020
Those who doubt the severity of Covid-19 often say that deaths from Covid are far less than from other causes. Figure 2 shows total deaths for the past two years to October as well as the average from 2015-2019 (as 2020 was very unusual), together with Covid deaths.
Figure 2: Covid-19 compared with all deaths per week
They have a point- to a point. Weekly deaths from Covid in 2020 and 2021 were tiny in comparison, but in 2022 have risen to be a fifth of the average number for this time of year. Breaking down the death toll to show separate diseases shows a different picture again.
Figure 3: Covid-19 and other major diseases
Clearly, Covid’s weekly death toll is already greater than all other major killers except cancer, and may overtake cancer in another couple of weeks. Thankfully we are close to the peak in eastern states.
Covid is a respiratory disease, but counted separately. How does it compare with other respiratory diseases? The next figure tracks Covid and total respiratory deaths, together with the average weekly deaths from respiratory illness from 2015 to 2019.
Figure 4: Covid-19 and respiratory disease mortality
Covid already not only exceeds the weekly respiratory deaths for any time in the last two years (which had very little influenza), but also the highest average for 2015-2019.
I used to think Covid-19 was just another nasty infectious flu. Not anymore. Here’s a comparison of Covid deaths with deaths due to influenza leading to pneumonia.
Figure 5: Covid-19 and influenza mortality
Already Covid-19 deaths are nine times the average for this time of year, and are also more than three times higher than the average in the peak of the winter flu season.
And WA has yet to open its border!
To compare mortality from diseases, the ABS calculates age-standardised death rates (SDRs) which “enable the comparison of death rates between populations with different age structures”. Rates are calculated per 100,000 population. Figure 2 shows death rates for the major diseases causing fatalities, including approximate (caution: not age- standardised) figures for Covid.
Figure 6: Death rates for Covid-19 and other major killers
Deaths will not stay at this high level for much longer. There are signs we are close to the peak of new cases, and deaths will peak a week or two after that. With Covid endemic in the community, mortality will fall to an unknown rate, and hospitalisations will become more easily manageable.
Make no mistake: this is a deadly disease! Take care!
Post Script: Here is another excellent resource: