“A straightforward analysis of data available suggests that confirmed active cases hugely under-report community infection.”
Those were the words of actuary Douglas Isles in a piece prepared for the COVID-19 working group of the Actuaries Institute. According to Isles, modelling suggests that there may have been around 20,000 carriers of the coronavirus in Australia as of April 09.
The figure is much higher than the number of active COVID-19 cases in the country, which stands at around 3,000.
Isles noted: “The focus in the media has been on three key data points around COVID-19: deaths, confirmed and active cases. We need to talk more about estimates and monitoring of community infection.
“Those risks need to be better understood before authorities decide when and how to relax current restrictions, an issue looming large for policymakers.”
Isles’ model made use of World Health Organisation data that tracked time lapses from the onset to recovery in various scenarios, as well as Australia-wide figures covering April 09 statistics plus rate of population testing, number of positive results, and recovery and fatality rates.
It was noted that using a constant carrier mortality rate and a constant timeframe from infection to death allows modellers to infer new carriers at a point in time.
“The Institute established a working group to help advise its professional members, industry, and policymakers who are seeking to understand the impact of the virus on our society and our economy,” said Actuaries Institute chief executive Elayne Grace.
“We are looking at community health aspects, but also how the virus impacts business sectors as diverse as health, insurance, and superannuation, and how policy changes may impact individuals, businesses, and communities.”
Grace added that the working group – which involves a core group of 13 actuaries who are supported by a further 50 actuaries – will also undertake assessments and approaches that can help in managing Australia’s eventual end to the lockdown period while ensuring that the impacts are as limited as possible.