Covid 19 coronavirus: NSW/Sydney daily infections on track to hit 500 by Friday, researchers say

A worker directs traffic outside the Bondi Beach drive-through Covid-19 testing clinic in Sydney on June 23. Photo / Getty Images

On this day one year ago, Victorian Premier Daniel Andrews stood before reporters in the middle of the state's deadly second wave and told Victorians the lockdown was working, "but too slowly".

"We must do more. We must go harder. It's the only way we'll get to the other side of this," he said.

A curfew was introduced that night, as were time, distance and gathering limits for shopping and exercise.

Victoria did get to the other side, but more than 800 people died in the process.

NSW now finds itself in the same position. Sydney is in lockdown as daily coronavirus cases rise above 200 and experts jostle about whether the current restrictions are hard enough.

New research from the Burnet Institute, published in the Medical Journal of Australia, suggests the only way to reverse the current trajectory of daily infectious cases is to crack down harder.

The researchers wrote that while a huge spike in cases had been avoided by measures introduced to date, cases will rise drastically if further measures are not introduced.

The dashed red line shows predicted daily Covid-19 cases in the absence of restrictions in Sydney. Image / Supplied

"When we ran [modelling] using trends in individual local health authorities, it predicted that by this Friday, 5 August, Sydney will record about 570 cases per day," they wrote.

"This is the result of stable or falling daily cases in southwest Sydney Local Health District (LHD) being exceeded by rising cases elsewhere. It takes about a week before new controls have an effect, so we don't expect new restrictions announced on 30 July to kick in until at least 7 August.

"Furthermore, unless new controls introduced on 28 and 30 July or in the future (eg. LGAs that develop large case numbers are included in the tighter controls) have a major impact, our model projects that Sydney will have about 7700 cases per day four weeks from now."

The modelling also reveals how bad things would have been in Sydney right now had the Berejiklian government chosen not to lock down when it did.

The authors, Professor Allan Saul, Professor Brendan Crabb, Doctor Campbell Aitken and Professor Margaret Hellard, wrote that cases have "trended steadily upwards over recent weeks" despite "increasingly tough restrictions".

They recommended "more consistent stringent restrictions, akin to those announced for the eight high-priority LGAs [in Sydney's southwest], uniformly across Sydney".

"Not only is this the equitable approach, but epidemiologically sound," they wrote.

NSW Premier Gladys Berejiklian: "Based on [today's community infection] numbers we can only assume that things are likely to get worse before they get better." Photo / Getty Images

The researchers created detailed models using data from what worked during Melbourne's second wave to get cases from more than 700 cases a day back down to zero.

They estimated that "without the progressive introduction of restrictions starting on June 26, including stay-at-home orders, further restrictions on July 9 and the closure of non-essential retail on July 18, Sydney would have recorded approximately 1000 cases per day by now".

"We calculate that the restrictions implemented so far have avoided 4000 cases, over and above the many prevented by contract tracing and subsequent isolation," they wrote.

Elimination goal out of reach?

One academic said it was possible NSW would become the first state to be forced to "live with the virus" and give up on the goal of zero community cases.

"NSW could be forced to bumble its way forward and play whack-a-mole until vaccination coverage is high enough so we can drive the outbreak down," Melbourne University epidemiologist Tony Blakely said.

"This year, we have a virus that spreads by fleeting transmission, it's way more likely to transmit in a coffee queue.

"There is an incredibly strong case for wearing masks outdoors whenever you're next to somebody. Why it's not mandatory across all of Sydney, I don't understand.

"If NSW was serious about eliminating the virus in the next six weeks, you would do everything you could."

NSW recorded 207 new cases today.

"Based on those numbers we can only assume that things are likely to get worse before they get better given the quantity of people infectious in the community," NSW Premier Gladys Berejiklian said.