Australia could use its defence forces to help manage a COVID-19 outbreak in the aged-care sector that has stretched staffing and forced many homes into lockdowns, the prime minister said on Friday as national infection numbers remained on a downtrend.

The government has come under pressure over the spread of the Omicron variant in aged-care homes, with Richard Colbeck, minister for senior Australians and aged care services, drawing criticism after he attended a cricket match instead of appearing before a parliamentary committee looking into the outbreaks.

Prime Minister Scott Morrison said he had asked the ministers of defence and health to see how defence forces could support care homes, where many staff have had to isolate because of infections.

Morrison said about 560 aged-care residents had died since Omicron hit in late 2021.

He told reporters the defence force was not a "shadow workforce" for the sector and cautioned against "simple solutions to complex problems" but said they had to consider options.

"When you're the prime minister, and the minister for health and aged care, and the minister for defence, you have to deal with practical options that work," he said.

The Australian Defence Force has been involved in managing the pandemic response, with a lieutenant general put in charge of the vaccine rollout and troops made part of the monitoring of lockdowns in big cities.

Total daily COVID-19 infections dipped across Australia on Friday and were on track to be the lowest in more than a month, with about 30,000 new cases logged in the biggest states.

With some states still to report figures, a total of 81 deaths had been reported on Friday.

(Reporting by Sam McKeith Editing by Robert Birsel)