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08 Nov 2021

Statement on the Doherty Institute modelling – final report to National Cabinet

Following the advice delivered to National Cabinet by the Doherty Institute-led modelling consortium on 30 July 2021 to inform the National Plan to Transition Australia’s National COVID Response (National Plan), the consortium was tasked with a second phase of work to support the implementation of the National Plan, which was approved by National Cabinet on 13 August 2021.

Presented to National Cabinet on Friday, 5 November, this second phase consisted of three work packages, which are outlined below along with the high level findings for each. The ‘Synthesis’ Technical Report and Attachments can be found on the Doherty Institute’s modelling hub.

Work Package 1: Modelling to inform review and refinement of public health response measures for optimal utility and sustainability in Phase B and beyond


  • With COVID-19 vaccination coverage greater than 70%, around half of all infections will be in vaccinated people, so milder and less infectious
  • Management of vaccinated cases and contacts can be simplified, but ‘Test, Trace, Isolate, Quarantine’ (TTIQ) remains critical for control
  • Ongoing evaluation of the impacts of TTIQ on transmission potential will be needed for situational assessment


Work Package 2: Optimise vaccination at sub-jurisdictional level, including attention to key populations and risk settings (First Nations, CALD and low SES communities, and schools)


First Nations

  • High levels of COVID-19 vaccine coverage can reduce transmission and health impacts in remote and urban communities
  • Reactive vaccine approaches are a useful adjunct to community engaged and led outbreak response
  • Providing access to effective treatments will further promote health outcomes

Local Government Areas

  • Baseline transmission potential differs by small area, as do COVID-19 vaccine and public health and social measure impacts (ability to work from home)
  • Focused TTIQ and wrap around supports will be needed to constrain transmission potential in high-risk areas


  • Early infection detection and high COVID-19 vaccine coverage markedly reduce outbreak risk
  • ‘Test to stay’ is equivalent to quarantine and enables face-to-face learning


Work Package 3: Review border measures and arrivals pathways in context of revised risk tolerance


  • COVID-19 vaccination reduces the risk of quarantine breach events, mitigating against shorter duration of quarantine
  • Breach importations do not materially impact on established epidemics or lead to large outbreaks where vaccine coverage is high if strain characteristics are equivalent