Cases of COVID-19 are still growing rapidly in Australia. We had 2,630 confirmed cases as of 25 March, up from about 700 a week before.
Pressure on health services is mounting. As we showed in a Grattan Blog post on March 24, if cases continue to grow at this exponential rate, Australia will hit capacity in hospitals Intensive Care Units (ICUs) in mid-April.
Major efforts are being made to boost the number of ICU beds across Australia. But the only thing that matters is the number of new COVID cases. If cases double every three days, doubling ICU capacity will only delay hitting the ICU cap by three days. Cases have been doubling every 3-to-4 days for the past three weeks.
While daily case numbers reported by each state are a bit jumpy, the number of new cases in Australia has flattened in the past couple of days. If this flattening trend continues — if lockdowns and spatial distancing are working and our cases numbers move from growing exponentially to linearly — the situation will be very different. But it is too early to tell if this is a genuine slow-down.
Australians do appear to be changing their behaviour in response to the spatial distancing and quasi-lockdown measures imposed by the state and federal governments over the past weeks. The chart below shows that the number of trips taken by people Melbourne and Sydney has fallen to about 25 per cent of normal.
But the number of trips has fallen further in other international cities with tougher spatial distancing restrictions. It is hard to believe that these Australian travel patterns reflect compliance with an injunction to stay at home except for essential trips.
Australians must be more compliant with spatial distancing measures. Analysis released this week by Chang et al (2020) shows that compliance rates of 80 or 90 per cent are required for spatial distancing to have the desired effect. The chart below shows that at even at 70 per cent compliance, the number of infections will continue to grow rapidly.
Whether the measures Australia has put in place will slow the spread here will not be known for about 10 days. By then, if our COVID-19 case numbers continue to rise exponentially, our ICU beds will have started to fill up. And, by then, any further lockdown measures will take another fortnight to have an effect. It will be too late.
We must continue to clamp down on the spread of COVID-19.