By Claire Matthews
Disease modelling experts at the University of Western Australia have identified the optimal time in a COVID-19 outbreak to introduce an early lockdown.
The modelling shows the best time for hard lockdowns to contain the growth rate and limit cases, hospitalisations and loss of life.
The researchers used computer simulation and maths to predict the exponential growth of an outbreak. The results showed that to prevent healthcare facilities from being overwhelmed, a hard stage 4 lockdown should be enforced at the first sign of cases increasing exponentially.
The modelling found that if Melbourne had immediately introduced a hard lockdown during its second wave last year, there would have been at least 60% fewer cases. Hospitalisation and deaths would also have decreased by a similar amount.
Professor Milne, from UWA’s Department of Computer Science and Software Engineering, said the research shows how important it is to catch increasing transmission rates before infections spread widely.
“This published study has provided hard evidence that going ‘hard and early’ is highly beneficial in an Australian setting, and this can now be used to guide both the Sydney and Melbourne outbreak responses.”
Using simulation technology, the study ran a range of different social distancing scenarios for the Melbourne 2020-second wave lockdown. This created a virtual world of individuals whose movement and contact patterns were recorded daily and modified by various stages of lockdown.
The UWA modelling program adapts an established seasonal influenza disease model based on a population of 270,000 in Newcastle, NSW.
Professor Mile said the recent findings showed that the Victorian Government should have moved to a harder lockdown, faster. Despite the social, economic and mental health issues of lockdowns, the science shows that it helps combat the virus in the long run.
“Hesitancy is understandable. Long-duration school closure impacts education outcomes, particularly among those from low socio-economic backgrounds.
“Closure of cafes, restaurants, and bars results in under-employment of young adults and has a knock-on effect on the economy. Closure of service and transport industries results in increased unemployment, with these measures and home isolation impacting the mental health of those affected.
“However, our results demonstrate the criticality of the timing of activation, where a slow response to rapid, exponentially growing case numbers allows the coronavirus to spread widely within the population, before the introduction of more robust social distancing measures can take effect.
“It’s the early control that potentially permits lockdown measures to be eased earlier.”
The solution is to establish a national coordination centre to compare outcomes of COVID-19 modelling to ensure the fastest and most effective response.