Leading expert on Covid lockdowns Catherine Bennett weighs in on Victoria cluster

One of the nation’s leading experts on Covid lockdowns has weighed in on whether a snap shutdown in Melbourne is necessary.

One of the nation’s leading experts on Covid lockdowns has questioned whether a snap shutdown in Melbourne is necessary, warning it has proven a “panicked” reaction by state premiers in the past.

Deakin University chair in epidemiology Catherine Bennett has told news.com.au that while longer lockdowns were successful in “crushing the virus” in the past, the value of shorter lockdowns was worth weighing carefully.

Victoria is considering a snap 5-day lockdown in response to the latest outbreak sparked by a man who is believed to have caught the virus while in hotel quarantine in Adelaide.

But as South Australia shut the border to Victoria on Wednesday night, some epidemiologists say a lockdown may not be required.

“They are insurance policies,’’ Prof Bennett told news.com.au.

“It doesn’t mean you have to have them, but it also doesn’t mean you also put them in place every single time.”

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Last of the Melbourne passengers arrive at Adelaide Airport before the 6pm lockdown on Wednesday. Picture: Mark Brake

Commuters are seen walking around Melbourne CDB. Picture: Luis Enrique Ascui

Recently, experts crunched the numbers on 17 Covid outbreaks in Australia since December, noting that six triggered snap state lockdowns, six were managed by gathering restrictions and five by contact tracing only.

The analysis found that four of the six lockdowns failed to detect any further cases not already isolated through contact tracing.

Only the northern beaches outbreak in Sydney and the Princess Alexandra Hospital outbreaks provided the exception to the rule.

Prof Bennett said the analysis underlined the fact that the shorter lockdowns were not responsible for “crushing the virus” as some state premiers claimed.

“For a long term lockdown that lasts for six to eight weeks, you can kill off the virus,’’ she said.

But she said the shorter, sharper lockdowns were really about “buying time” for contact tracers.

“A circuit breaker isn’t built for that. A circuit breaker is allowing the health department to get on top of it, to catch up,’’ she said.

“So you’re just shutting everything down to the viruses without running on too much further until you catch up with that so it’s buying time.”

Prof Bennett said that the fact that the new Covid cases in Melbourne were all linked to the existing cluster was a “promising” sign.

“At the moment, they’re not seeing any cases outside the very close contacts,’’ she said.

“If they saw cases that were people who only had a casual exposure, that would send some alarm bells going off because we’ve got a lot of casual contacts.

“And if we thought it could spread that easily, and we had evidence, that would trigger a lockdown.

As the speculation over a Melbourne lockdown escalates, Scott Morrison has also lashed out at his COVID-19 vaccine rollout critics as “whingers and complainers”.

“I don’t know what world those sleepwalkers opposite are living in,’’ he said in question time.

“I don’t know what world they’re living in. But I know every Australian is very happy to be living in Australia during the course of this pandemic,’’ he said.

“Those opposite, Mr Speaker, may want to retreat into whinging and complaining and undermining the government, as we fight the virus and they focus on the politics.”

Earlier, Labor leader Anthony Albanese attacked the Prime Minister over the Victorian outbreak suggesting the Morrison Government needed to act.

“How many more outbreaks do there have to be until the Prime Minister understands that he needs to do his job and deliver a safe, national, purpose-built quarantine system and fix his bungled vaccine rollout?,’’ Mr Albanese asked.