COVID-19 Mortality in Australia, Deaths registered to 31 October 2021

• 1,671 deaths due to COVID-19 that occurred by 31 October 2021 have been registered by 30 November and received by the ABS. The ABS expects to receive further registrations for this period from the jurisdictional Registries of Births, Deaths and Marriages.
• The 1,671 deaths include 16 that were suspected as being due to COVID-19 with the virus not confirmed in a laboratory.
• Most COVID-19 deaths had acute respiratory symptoms such as viral pneumonia or acute respiratory distress syndrome listed as a consequence of the virus.
• 71.2% of people who died from COVID-19 had pre-existing chronic conditions certified on the death certificate.
• Chronic heart diseases were the most common pre-existing chronic condition for those who died from COVID-19.

The Coronavirus Disease 2019 (COVID-19) is a respiratory infection caused by a new coronavirus. On 11 March 2020 the World Health Organization (WHO) declared COVID-19 to be a pandemic. There were 1,671 people who died from COVID-19 between the start of the pandemic and 31 October 2021. 

In Australia, information on deaths from COVID-19 is collected through both civil registration systems and disease surveillance systems. Disease surveillance systems provides rapid information on both infections and mortality.

Mortality data compiled by the ABS is not based on this daily surveillance. Instead, it is based on death registrations processed by the jurisdictional Registries of Births, Deaths and Marriages, and information on the cause of death sourced from a Medical Certificate of Cause of Death (MCCD) completed by a certifying practitioner.

Mortality data tabulated from the disease surveillance system and the registration system are not directly comparable.

While it takes longer to get the information from the registration based system than the surveillance system, it is more comprehensive and can provide important additional insights into deaths from COVID-19. This is especially the case with data obtained from the MCCD, which enables identification of the underlying cause of death and other associated causes. These data sources also provide demographic information about the decedent (e.g. age, sex and usual residence).

There were 1,744 deaths which occurred by 31 October 2021 and referenced the COVID-19 virus on the death certificate. Of these 1,744 deaths, 1,671 were deaths due to COVID-19, including:

• 1,655 which were directly due to COVID-19 with the virus being laboratory confirmed, six of which were from long term complications of COVID-19. 
• 16 deaths that were certified as being due to suspected COVID-19 with the virus not confirmed in a laboratory at the time of certification.

These 1,671 deaths are included in COVID-19 mortality tabulations in this report.

Other deaths that had COVID-19 as a term on the death certificate included:

• 16 deaths which were COVID-19 related. This is where the person died with COVID-19 or a long term effect of the virus (confirmed or suspected) but it was not the underlying cause of death.
• 48 deaths which had a negative COVID-19 result recorded on the death certificate. When a negative COVID-19 test result is recorded on a death certificate an ICD-10 code of ‘Z03.8 Examination and observation for other specified reasons’ is assigned to capture the information communicated by the doctor.
• 9 deaths which occurred in people who had COVID-19 but recovered. These mentions of COVID-19 on the death certificate are captured with an ICD-10 code of “U08.9 Personal history of COVID-19”.

These 73 deaths are not due to COVID-19 and are not included in tabulations in this report.

Australian cause of death data is coded to the International Classification of Diseases, 10th revision which is governed by the WHO. Case definitions, certification guidelines and coding rules have been implemented for international use.

A death directly due to COVID-19 is defined by the WHO as a death resulting from a clinically compatible illness, in a probable or confirmed COVID-19 case, unless there is a clear alternative cause of death that cannot be related to COVID disease (e.g. trauma). There should be no period of complete recovery from COVID-19 between illness and death.

In response to the emergence of COVID-19 the WHO issued new emergency codes to be used when coding causes of death for statistical purposes.

• U07.1 COVID-19 virus identified

This code is used when COVID-19 is confirmed by laboratory testing.

• U07.2 COVID-19 virus not identified

This code is used for suspected or clinical diagnoses of COVID-19 where testing is not completed or inconclusive.

• U08 Personal history of COVID-19

This code is used when a person has recovered from COVID-19 and no long term effects have been certified as contributing to an individual’s death. These deaths are not included in COVID-19 mortality tabulations.

• U09 Post COVID-19 condition

This code is used to link long term conditions including chronic lung conditions that are the result of the virus. These deaths are included in COVID-19 mortality tabulations.

• U10 Multisystem inflammatory syndrome associated with COVID-19

This code is used to identify people who have died from COVID-19 where the virus has led to a multi-inflammatory response syndrome. There have been no deaths due to this disorder in Australia.

A further code ‘Z03.8 Examination for observation and other specified reasons’ can be used to record a negative test result in order to capture this information on the death certificate. These deaths are not tabulated as being due to COVID-19.

The international rules and guidance for selecting the underlying cause of death for statistical tabulation apply when COVID-19 is reported on a death certificate. COVID-19 is not considered as due to, or as an obvious consequence of, other diseases and conditions. These rules are also applied to cause of death coding for Influenza and selected other infectious diseases. Further, there is no provision in the classification to link COVID-19 to other causes or modify its coding in any way.

Almost all deaths due to COVID-19 in Australia have laboratory confirmation of the virus. Of the 1,671 registered COVID-19 deaths occurring by 31 October 2021, 1,655 (99.0%) were coded to U07.1, (laboratory confirmed) COVID-19, virus identified. There were 16 (1.0%) deaths where the doctor certified that it was a suspected case of COVID-19 with no laboratory confirmation recorded at the time the MCCD was completed.

• Males had a higher number of registered deaths (883) due to COVID-19 than females (788 deaths).

• The highest number of COVID-19 deaths occurred among those aged 80-89 years (612). This was true for both males and females.

• Males aged under 80 years had a higher number of deaths than females (401 compared with 232).

• The median age for those who died from COVID-19 was 83.7 years (81.2 years for males, 86.0 years for females).

The case fatality rate (CFR) can provide an indication of the severity of a disease. For COVID-19 it is calculated by dividing the number of deaths by the number of confirmed infections. The overall CFR for Australia for COVID-19 as of 31 October 2021 was 1.0%. The CFR can differ by key demographics. The graph below shows that while the CFR for those aged under 60 years is 0.1%, the CFR for males aged 90 years and over is close to 50%.

As of 31 October 2021, most deaths due to COVID-19 occurred in Victoria (1,084). There were less than 10 deaths in both Queensland and South Australia, and none in the Northern Territory. 

COVID-19 was the underlying cause of death for 1,671 registered deaths occurring up to 31 October 2021. The WHO defines the underlying cause of death as the disease or condition that initiated the train of morbid events leading to death. Diseases and conditions reported on the MCCD that are not the underlying cause of death are referred to as associated causes. Associated causes can be either:

• Conditions listed in the causal sequence (the chain of events leading to death); or
• Pre-existing chronic conditions, often listed in Part II of the MCCD as ‘other conditions relevant to the death’.

Examining conditions in the causal sequence can provide insights into how a disease progresses and leads to death. Examining pre-existing chronic conditions provides an understanding of risk factors that might contribute to death from a particular disease. Both can inform health prevention and intervention policies.

Most deaths due to COVID-19 have other conditions listed on the death certificate (91.0%). The table below shows that over two-fifths of all certificates had both a causal sequence and pre-existing conditions listed on the certificate.

On average, deaths due to COVID-19 had 2.6 other diseases and conditions certified alongside the virus. 

COVID-19 is a respiratory illness that weakens the immune system causing inflammation. This commonly leads to poor respiratory outcomes such as viral pneumonia and secondary infection. Other manifestations such as acute kidney injury have also been reported but these are less common.

Disease progressions were described in a causal sequence by the certifier in 1,096 (65.6%) of the 1,671 COVID-19 deaths covered in this report. Among these 1,096 deaths:

• Acute respiratory diseases (including pneumonia) were the most commonly certified diseases listed as a consequence of COVID-19.
• Pneumonia was present as a consequence of COVID-19 in over two-thirds of deaths where a causal sequence was certified.
• Infections (e.g. sepsis) and renal complications were certified in 10.3% and 7.4% of deaths.

People with pre-existing chronic conditions have greater risk of developing severe illness from COVID-19. While pre-existing chronic conditions do not cause COVID-19, they increase the risk of COVID-19 complications and therefore increase the risk of death.

Pre-existing chronic conditions were reported on death certificates for 1,189 (71.2%) of the 1,671 COVID-19 deaths covered in this report. Of these 1,189 deaths:

• Chronic cardiac conditions including coronary atherosclerosis, cardiomyopathies and atrial fibrillation were the most commonly certified comorbidities, present in over 35% of deaths.
• Dementia was present in 31.8% of deaths.
• Diabetes, a condition that weakens the immune system, was certified as a pre-existing condition in 20.9% of deaths.
• Cancer was a pre-existing condition in 12.6% of deaths. Blood and lymph cancers (e.g. leukaemia) were the most commonly certified cancer type among those deaths. 
• The types of comorbidities most commonly present in Australian deaths due to COVID-19 are consistent with those reported internationally.

​​​​​​​Age-standardised death rates enable the comparison of death rates across populations as they account for differences in the size and age structure of the population.

• Those who died of COVID-19 with a country of birth overseas, had an age-standardised death rate over double that of people who were born in Australia (4.3 deaths per 100,000 people versus 1.6).
• Those born in Samoa had the highest age-standardised death rate at 37.3 deaths per 100,000 people.
• Those born in England had the lowest age-standardised death rate at 1.0 per 100,000 people.
• By region, North Africa and the Middle East had the highest age-standardised death rate at 16.3 per 100,000 people, with over 40% of the deaths in this group occurring in those born in Lebanon.
• Those born in the Eastern European region had the highest median age at death at 92.1 years. Those born in the Oceania region (excluding Australia) had the lowest median age at death at 68.0 years. 

Socio-economic indexes rank areas in Australia according to relative socio-economic advantage and disadvantage. This analysis uses the Index of Relative Socio-economic Disadvantage (IRSD) to measure socio-economic status. 

• The number of people who died due to COVID-19 was over four times higher for those in quintile 1 (most disadvantaged) when compared to those in quintile 5. This was true for both males and females.
• Proportions and numbers of COVID-19 mortality was similar for both males and females across each quintile.
• People living in the least disadvantaged areas (quintile 5) had the lowest numbers of deaths due to COVID-19.

14/4/2022 - The title of this article has been updated from 'COVID-19 Mortality' to 'COVID-19 Mortality in Australia, Deaths registered to 31 October 2021'