Australia's tally of people with the new Omicron variant of Covid-19 has edged higher, prompting state governments to bolster domestic border controls as health experts wait to learn more about the dangers posed by the strain, Reuters reports.

The country's most populous state, New South Wales, reported its seventh case of the variant, a person who arrived on November 23 from Doha, Qatar, and noted that the person had not been in southern Africa, suggesting they caught the virus on the flight.

While the Australian federal government has urged states to avoid a return to the stop-start lockdowns that have defined the country's virus response, health authorities have urged caution until they knew more about Omicron's infectiousness and virulence.

"We know this virus is dangerous, it does come out in some different forms," New South Wales Health Minister Brad Hazzard told reporters. "Don't take it lightly."