Australia's chief scientist says Victoria's contact tracing system was easily overwhelmed during the state's second wave of coronavirus.
Dr Alan Finkel told a parliamentary inquiry into the state's contact tracing system on Wednesday the system was only prepared to manage low case numbers.
"It all comes to preparation and there's no question the Victorian system was overwhelmed," Dr Finkel said.
"Cases weren't being managed end to end, some were lost, duplications occurred - it was difficult."
Dr Finkel said prior to the pandemic, Victoria's centralised pen and paper system was only prepared for low cases of measles and other infectious diseases.
"Then you're hit by a pandemic with large numbers that are doubling every four or five days. Unless you are fully prepared for that ... it's easy to get overwhelmed," he said.
The Victorian government has since recruited tech giant Salesforce to provide a digitised system covering the whole contact tracing process - from test results to interviews, phone calls, and the management of cases and contacts.
Six local contact tracing hubs have also been set up across the state.
Dr Finkel described the new system as "more efficient and less error-prone".
He said if Victorian authorities had such systems in place prior to the second wave, "they might not have gotten to the point of breakdown".
Dr Finkel has conducted a review of the nation's contact tracing.
He believes all jurisdictions had improved their capability, with health authorities across Australia now training to manage 50 cases for a sustained period per day, per million people.
It means Victoria is training to manage up to 350 cases per day.
"That's not easy to do but we do believe it's achievable through having surge workforces in place already trained and already authorised to do the work, the technology in place to make each person's contribution as efficient as possible," Dr Finkel said.
Each state is also aiming to return COVID-19 test results within 24 hours, with no more than 48 hours between the time a test sample is collected and close contacts notified.
"We should not be surprised that the coronavirus will appear in our community from time to time, as we've seen in the last few days in Parafield, following nearly six months in South Australia without a case in the community," Dr Finkel said.
The Legislative Council Legal and Social Issues Committee, chaired by Reason Party MP Fiona Patten, is investigating whether the contact tracing system as it stands can handle future coronavirus outbreaks.
Public hearings continue.
