South Australia's COVID-19 modelling – Professor Nicola Spurrier – April 2022

SA Health has today released updated modelling undertaken by Professor Joshua Ross and Dr Thomas Prowse at the University of Adelaide, which projects the impact of COVID-19 and the Omicron variant in South Australia.

We have consistently reviewed and recalibrated our modelling as the COVID situation evolves in the state as we input our local SA data. It’s an important tool to help us plan our health system response and accounts for changes in vaccination rates, public health and social measures, and isolation and quarantine.

Readjusted data shows South Australia will most likely have a peak of around 5,500 cases a day, rather than upward of 8,000 as previously calculated.

The latest model has altered the assumptions of the impact of lifting restrictions on disease transmission. While it is difficult to predict human behaviour, this is a good indication that South Australians are continuing to do the right thing such as staying home if unwell and keeping up with COVID-safe behaviours while out in the community.

The updated modelling also outlines the number of hospitalisations for COVID-19 and this is good news with less hospitalisation than first estimated. It is possible this is due to the BA.2 sub-variant being less severe than BA.1, but we do not know that yet. People are also keeping out of hospital by getting treated with oral antivirals and we are using alternatives to hospital care for many people now.

Our hospital staff are still working very hard because people admitted with incidental COVID (when a COVID positive patient is hospitalised for other health reasons) need a higher level of PPE and isolation from others.

It is still a little early to tell if we have reached the peak of the Omicron wave, but watching the case numbers over the next few days may help in this regard.