Just 10 days ago the prime minister told reporters on the Eden-Monaro election campaign trail Australia couldn't let the virus hold it back.

That same day, residents across more than 30 suburbs of Melbourne were put back into lockdown.

This week, NSW shut its border to Victorians - although by mutual agreement, unlike the South Australian side that has been restricted since April.

And the entire greater Melbourne region returned to the toughest level of business closures and stay-at-home orders.

Many businesses managed to reopen their doors only for a week or two before being forced shut again - the very stop-start the prime minister insisted we could avoid.

The way this insidious virus spreads so quickly and easily means the idea outbreaks could be contained simply by pausing planned measures to restart the economy instead of clamping down and stopping people gathering again was nonsense.

"This is a virus that doesn't, you know, communicate itself in terms of its intentions or how it's going to behave," Morrison said on Wednesday.

"We don't have control over the virus, as such, but we do have control over how we respond."

The challenge with this potential second wave of infections will be to swiftly learn what worked and what didn't the first time and act without giving in to the temptation for political recrimination.

Imagine if the outbreak had occurred in Queensland, which has a state election in October?

Federal coalition politicians - especially Peter Dutton - already spare few opportunities to take potshots at Labor premier Annastacia Palaszczuk.

But there are questions about the new outbreak that need answers.

How did the hotel quarantine arrangements in Victoria go so wrong? Why were private security contractors used there instead of police and the defence force as in other states? Why were nearly a third of people allowed to refuse coronavirus tests?

While national cabinet jointly decided to require quarantine for travellers from overseas, Australia is a nation of states and arrangements were managed individually by each jurisdiction.

People returning from overseas who waited out their quarantine periods in Sydney or Perth tell of being completely confined to their hotel room, having to pace around the beds for exercise and rely on friends for deliveries of care packages.

Yet there are reports that infections spread from quarantined people in Melbourne to security guards - then out to their families, friends and communities - via shared cigarette lighters and alleged intimate contact.

Freelance reporter Megan Clement wrote on Twitter last weekend that even amid all the focus on infection spikes and quarantine arrangements, guards and hotel staff where she was in quarantine still seemed to have little training in infection control.

"We are being assured of a reset but a guard came to my door without a mask to hand me a delivery last night," she wrote.

Victorian Premier Daniel Andrews has announced a judicial inquiry into quarantine arrangements but it is clear changes need to be made faster than that can happen.

Top health officials are doing an urgent review of hotel quarantine arrangements for national cabinet to consider on Friday.

Morrison has also flagged the trickle of international flights returning to Australia will be slowed even further so as not to overwhelm quarantine now Victoria has been taken out of the equation.

Over the past month, Victoria has taken responsibility for one in five returned travellers, almost 15,400 people.

Meanwhile, counting hasn't even finished in the Eden-Monaro by-election and what seemed vitally important a week ago has already faded from sight.

In the end, the status quo prevailed - both in terms of the party holding the seat (Labor) and the votes, with the margin dropping from a large handful of votes to a small fistful.

This was no 2018 super Saturday leader-vs-leader showdown, much as the coalition commentators on the election night broadcasts might have wished it to be.

The race in the former bellwether seat seems to have joined the location of the AFL grand final as one of the furthest things from Morrison's mind right now.

Australian Associated Press