20% reduction in COVID transmission could save 2,000 Australian lives this year

Australia’s COVID death toll is rising, yet public health measures to reduce transmission such as mask requirements are largely a thing of the past.

It is time for governments and the community to consider what measures can be reinstated to reduce transmission and deaths from COVID, especially during waves of infection.

A 20% reduction in COVID transmission could prevent more than a million infections and 500 COVID deaths in Victoria this year, our new modeling shows.

Given that Victoria accounts for around 25% of Australia’s population, these results, when extrapolated, suggest that a 20% reduction in transmission could save up to 2,000 lives nationwide.

Even if the reintroduction of public health measures reduced COVID transmission by 10%, it could save between 198 and 314 Victorian lives by the end of 2022. This too would save many more lives nationwide.

Read more: COVID has killed 5,600 Australians this year and the pandemic isn’t over yet. Ethics can shape our response

COVID isn’t ‘just like the flu’

The prevailing view in Australia is that we can now treat COVID ‘like the flu’. However, the dramatic and sustained spike in COVID-related deaths in 2022 tells a very different story. 5,687 COVID deaths have been reported in Australia since January 1.

During the Omicron wave of January 2022, COVID was the second leading cause of death nationwide, with 2,865 more deaths than normally expected that month. That’s an increase of 22%.

Crucially, COVID deaths have not stopped since peaking in January: our current seven-day average is about 45 deaths per day, or 315 deaths per week.

In comparison, our last severe flu season (2017) caused 1,255 deaths for the entire year.

We have vaccines, so why are there so many deaths?

There are still so many deaths because we let the virus run. By scaling back public health measures and delivering an “it’s over” message, we’ve enabled near-unrestricted transmission.

381,000 Australians are currently known to be infected with SARS-CoV-2, the virus that causes COVID. With high case numbers comes a high death toll, even with a reduced case fatality rate (the proportion of those infected who die).

This relaxed political stance – combined with emerging variants (three new Omicron strains have arrived in Australia), winter encouraging more indoor living, and waning immunity – suggests the high case numbers will continue for some time to come.

Who dies from COVID?

In order to reduce COVID deaths, it is important to understand who is dying and why. While some basic information on deaths is available for some states, additional data is needed — for example, whether the deceased are eligible for antiviral treatment. Such data could enable targeted public health actions, e.g. B. Improving access to treatment.

However, based on the data we have, we know that older people remain the most vulnerable. Last week, despite very high vaccination rates, NSW recorded 41% of all COVID deaths among aged care residents.

Read more: Australia is failing marginalized people and it shows in COVID death rates

We often hear that those who die from COVID have pre-existing conditions. That’s right — about 70% of deaths from COVID have occurred in people with chronic conditions.

However, keep in mind that half of all Australians, as well as 80% of those over 65, suffer from a chronic condition. Given that most of those who have died from COVID are over the age of 65, it is not surprising that most also have an underlying condition.

Are people more likely to die “with” than “of” COVID?

Some argue that the high rates of COVID deaths are not as worrying as they seem because people are dying “with” COVID and not “from” COVID.

But the majority (89.8%) of COVID deaths are “due to” COVID.

For those defined as dying “with” COVID, this means that COVID may or probably “contributed” to those deaths.

For example, a person is infected with COVID, which weakens their immune system and leads to bloodstream infection (sepsis). They are hospitalized and die three weeks after their COVID diagnosis. Although her death is directly “due to” sepsis, it is also “with” COVID because COVID caused the decline in her health that ultimately led to her death. COVID is no coincidence in these deaths.

The doctor in the intensive care unit looks at the computer screen.
Most COVID deaths are “from” COVID.
Kate Geraghty/AAP

COVID is also killing young people – even children. Eight children aged nine and under have died from COVID in Australia since the pandemic began, as well as five people aged ten to 19, 22 in their 20s and 65 in their 30s.

It is impossible to know if COVID will cause a significant number of premature deaths in the years to come. Given the damage the SARS-CoV-2 virus is doing to the heart, brain, kidneys and lungs, we have reason to be seriously concerned.

What could reduce the COVID fatality rate?

Vaccination is still hugely important and the main reason why we can even consider our current open lifestyle. But vaccination alone is not enough.

Improving air quality and/or wearing a quality N95/P2 mask indoors causes minimal community disruption but effectively disrupts COVID transmission.

To illustrate the utility of interventions, we used our model to simulate three hypothetical scenarios for the state of Victoria for the remainder of 2022.

We first modeled a scenario with no additional interventions (the light blue line). We compared this to two scenarios that introduced hypothetical interventions starting May 20 that could reduce the risk of transmission per contact by 10% (the dark blue line) or 20% (the red line).

We did not indicate what specific interventions should be taken to offset the 10 percent or 20 percent reduction. It could be a single intervention or a combination that accounts for the 10 to 20 percent reduction.

Measures to reduce transmission by 10% or 20%.  Data represents Victoria only and shows projected infections, not COVID diagnoses.

Burnet Institute, Author provided (no reuse)

Between 20 May and the end of 2022, the outcomes of the no additional interventions scenario were an additional 2.22 to 2.38 million infections or reinfections and 1,060 to 1,450 deaths in Victoria.

Interventions that reduce transmission by 10% could avert 596,000-614,000 infections and 198-314 deaths over this period (a 16-25% reduction).

Interventions that reduce transmission by 20% could avert 1.08-1.10 million infections and 462-502 deaths (a 37-40% reduction). As described above, this means up to 2000 lives nationwide.

These are likely to underestimate the effect of interventions, since the analysis was deliberately conservative and did not take into account any new COVID variants or subvariants (only omicron BA.1 and BA.2).

The simple message is that a small reduction in transmission has a large impact on mortality.

How do we do this modelling?

The model used for this work was COVASIM, a model that can assess the impact of different policies and behaviors on COVID transmission, hospitalizations, and deaths. The model has been used to support policy decisions in Australia, the United States and the United Kingdom.

Individuals in the model are assigned an age (which affects their susceptibility to infection and disease prognosis), household, school (for individuals aged five to 17), or job (for individuals aged 18 to 65) and they take Participate in a range of community activities which may include going to restaurants, pubs, places of worship, community sports and social gatherings.

The model includes:

  • Vaccination (including individual dosing regimens, vaccine types, and declining immunity)
  • Tests (PCR or rapid antigen tests)
  • Contact tracking (self-tracing)
  • Quarantine of close contacts
  • Isolation of confirmed cases
  • masks
  • a variety of policy restrictions to prevent or reduce transmission in different settings (eg, school or workplace closures, hospitality and retail density limits, social gathering size limits).
Woman in a mask shop for clothes.
The COVASIM model assesses the impact of different policies on behavior and COVID transmission.

It’s not just about the economy

Australia has successfully mitigated the direct impact of COVID in the first two years of the pandemic. Recently, however, Australia has made little effort to reduce the impact of COVID. We tacitly, perhaps unknowingly, endorse a trade-off between COVID deaths and economic and social well-being in general.

Many people seem unaware of the high death toll and that simple interventions can make a significant difference.

But the value of the current compromise is unclear. The economic and social benefits of rolling back key public health measures when tens of thousands of COVID cases are occurring every day have not been demonstrated. In fact, reports of major COVID-related disruptions are rife, suggesting the opposite is true.

Australia needs to find a middle ground focused on slowing transmission, reviving vaccine rollout and expanding treatment options for people with COVID infections. Otherwise, 10,000 or more COVID deaths a year could be our new – previously unthinkable – normal.

Read more: I’m at home with COVID. When do I have to see the doctor? And what treatments are there?

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