Almost all current cases of Covid-19 in Victoria, Australia, can be linked to returned travellers quarantined in the state, an inquiry has heard.
The inquiry also heard guards at quarantine hotels were given “inappropriate” training advice.
Australian media report that guards were told masks and other protection would not be necessary, as long as they adhered to 1.5m social distancing.
Victoria is currently in lockdown because of a second wave of infections.
Stricter “stage four” restrictions were put in place in the city of Melbourne on 2 August for six weeks.
On Monday, Victoria recorded 25 more deaths and 282 new cases of the virus, making it the state’s deadliest single day since the start of the pandemic.
At the end of March, Australia’s federal government said everyone returning to the country from abroad would need to enter mandatory quarantine programmes, which would be run by individual states.
Prof Ben Howden, director of the Melbourne-based infectious diseases centre Doherty Institute, told the inquiry into Victoria’s hotel quarantine system that genomic sequencing data suggested that at least 99% of cases at the end of July could be traced to people who had returned after travelling abroad.
However, he did not specifically link the cases to people in these programmes or to any particular hotels.
The sequencing looked at 46% of the state’s cases up to 23 July, he said, adding that they were “incredibly confident about the accuracy of that clustering”.
Barrister Tony Neal QC said the inquiry would aim to determine how the programme was structured and who was ultimately responsible for running it, as well as what improvements could be made for future quarantine programmes.
The quarantine programme “fell short of its goal” of preventing the spread of Covid-19, and for some people in quarantine it was “not clear who was in overall command of the operation”, Mr Neal said.