More than a quarter of Australia's total cases were recorded in the last four days, largely attributed to the arrival of the highly infectious Omicron variant in December.

Compared to the rest of the world, Australia is late to the marker.

As of January 7, the United Kingdom had passed 14 million cases while the United States was nearing the 60 million mark.

Yet UNSW infectious diseases associate professor David Muscatello says counting the number of cases is becoming impractical.

"You'll never really know the true number of cases because the only ones we know are the ones we're testing for," he told AAP.

"With the rate cases are occurring, I think it's going to be a worldwide trend to move away from counting each one and rather we'll focus on hospitalisations."

As the peak of the latest outbreak looms, so too does the federal election where health care is expected to be a key issue.

Prime Minister Scott Morrison told reporters on Monday: "Omicron changed everything."

"Delta was a completely different variant of this virus, and so, as we have had to do on so many occasions during this pandemic, rules that were written for one situation have to be reconsidered," he said.

Dr Muscatello says it would have been difficult for anyone to predict the arrival of Omicron.

"In human history we have never seen a virus evolving in real time, we've never had the scientific ability to watch what's happening," he said.

"Australia has done very well with getting people vaccinated and in the end we're in the best position we could be."

Former senior federal health advisor Troy Bilsborough says health care influenced more votes than any other issue at the 2019 federal election and he expected the current outbreak to do the same.

"We've also seen roughly five months between the arrival of new variants like Delta and Omicron, meaning the major parties could be facing a likely May federal election in the midst of a new outbreak, not just this one," he said.

Australia's fatality rate from the virus has also remained low compared to other countries, with less than 2500 deaths reported during the entire pandemic.

Going forward, Dr Muscatello says it's helpful to focus on what we know now rather than trying to predict what will happen in the future.

Keeping up with the prevention practices we've all become used to over the last few years is the key to living with the virus, he says.

"It's very hard to eliminate the risk but there are things you can do to reduce the risk," he said.

"Getting your booster, physical distancing, wearing a mask, hand hygiene are all really important."

Australian Associated Press