Australia has suffered its deadliest day of the coronavirus pandemic yet, with the deaths of 25 more Victorians.

The state has also had 282 new COVID cases in the past 24 hours – continuing a trend of falling infections as Melbourne’s Stage 4 restrictions appear to be having an effect.

It is the rising death toll that remains most concerning, with the virus claiming 107 Victorian lives in just the past week. There are still 651 COVID patients in Victorian hospitals, 44 in intensive care.

Premier Daniel Andrews said those who had died were: A man in his 60s, four women and three men in their 70s, six women and four men in their 80s, four women and three men in their 90s.

Victoria’s virus death toll is 334. Nationally, 421 people have died.

Mr Andrews said that while many of the fatalities were older people, the virus remained a challenge for the wider community.

“It’s better news though, of course, to have another sub-300 day is good in terms of that trends and the general movement down towards the lower case numbers,” he said.

“We are strong, there is good cause for people to be hopeful about the future. We just can’t allow any sense of complacency to creep in here.”

Melbourne is beginning its third week of a six-week shutdown of all but essential businesses. Regional Victoria faces Stage 3 measures.

On Monday, a leading infectious diseases expert revealed when he thought the Stage 4 lockdown should ease.

Professor of infectious diseases at the ANU’s Medical School, Professor Peter Collignon, who is on the board advising the federal government on the pandemic, told Melbourne radio 3AW that Victoria’s new cases must fall to 10 or 20 a day “before you think about dropping anything majorly”.

“It may well be that once numbers look like there’s a trend that’s continuing you can go back at least one level to the previous level of lockdown,” he said.

In positive news, Professor Collignon said Victoria appeared to have passed its COVID-19 peak.

“When we look at what we call the five-day moving average, I think actually you probably have turned in Melbourne and Victoria,” he said.

“It’s not falling very fast but it is falling … that fall should continue.”

Infectious diseases expert Peter Collignon said Melbourne appeared to be past its virus peak. Photo: AAP

Victoria’s five-day average of new infections has dropped to 303 as daily case numbers have fallen from a peak of 725 on August 5.

Elsewhere, a professor who delivered a scathing assessment of Victoria’s health system was to give evidence at the inquiry into the state’s hotel quarantine program on Monday.

Failures in the scheme are believed to be responsible for the Victoria’s second wave of COVID-19.

Infectious diseases expert Lindsay Grayson is among three witnesses to appear at the inquiry’s first public hearing on Monday.

Professor Grayson wrote a blistering comment piece in The Age newspaper in July.

“It’s time to discuss the reality – namely, that the Victorian health department is one of the worst-funded and dysfunctionally organised in the nation,” he said.

He praised staff, singling out chief health officer Brett Sutton.

“But the system they work in is paper-thin,” Professor Grayson said.

He is professor of infectious diseases at the University of Melbourne and director of infectious diseases and microbiology at Austin Health.

Professor Ben Howden from the Doherty Institute and Dr Charles Alpren from the Department of Health and Human Services will also give evidence on Monday.

The $3 million inquiry, headed by retired judge Jennifer Coate, will report in November.

Front-line doctors have also told how they warned about infection dangers inside the hotel quarantine program more than a month before workers started catching COVID-19. The DHHS never responded to their concerns.

Travellers in hotel quarantine ‘horrified’

A Four Corners investigation on Monday night will reveal the Australian Medical Association wrote to the DHHS on April 15, recommending infection control measures to stop returned international travellers transmitting the deadly virus to workers and the public.

The email were written after health workers involved in looking after COVID-19 patients in hotel quarantine began raising concerns.

“We had a whole host of concerns around how the hotel quarantine system was being managed, in terms of resourcing and also in terms of the protocols being used,” AMA Victoria president Julian Rait said.

“The department wasn’t really perhaps as conscious of the need to have the proper infection control protocols around the security personnel.

“We really needed to have someone checking the compliance of their behaviours to make sure that they followed the right processes.”

Queensland nurse Christine Cocks, who was in hotel quarantine in Melbourne, has told the ABC she was concerned about security guards’ exposure to the virus. She also said travellers were horrified at the state of rooms they were to be quarantined in.

“When we arrived in our room and saw the fine layer of dust across the top of the bar and the shelves there, and the dirty table, the dirty desk, we had a feeling that things might not have been as clean as we were expecting, and that the handling of the whole situation might not be up to what it should have been,” she said.

“Some people had stains on their sheets, as if the sheets were dirty.

“There were a couple of rooms that had bedbugs. Another person said that there was faeces in the toilet that hadn’t been flushed, and urine splattered on the floor around the toilet, that she had to clean.”