Harsher restrictions, national emergency declared. What next to set us free again?

COVID-19 case numbers continue to climb across Sydney, with 136 cases recorded overnight — a record high for 2021. NSW Premier Gladys Berejiklian described the situation as a “national emergency” as she called for the federal vaccine rollout to focus on Sydney.

It’s not clear what labelling the outbreak a “national emergency” will do. The National Emergency Declaration (Consequential Amendments) Act was legislated only last year after the bushfire royal commission and can be declared by state and territory administrators if “extraordinary measures are required to prevent or minimise the effect, or likely effect, of that emergency on the territory”.

It could signal harsher restrictions for the state, with more residents in Sydney’s west not allowed to leave their local government area unless they’re on a list of authorised workers.

Experts have criticised Berejiklian for being too slow to go into lockdown and too lax with restrictions. With more than half the country’s population in lockdown because of Sydney’s outbreak, what more could be done to stamp out case numbers? And is there any evidence to back it up? 

Masks outdoors

Victoria has mandated that everyone must wear a face mask at all times except when at homes or exercising, provided the exercise is strenuous enough for the person to be out of breath or puffing. But joggers must have a mask on them at all times. 

NSW also mandates that everyone must have a face mask on them at all times, but they only have to be worn outdoors when near others. 

A new study released yesterday by the Burnet Institute showed the mask mandate in Victoria was key to reducing transmission; mask usage rose from about 43% to 97% in the four days after the mandate was enforced. 

One study found face masks indoors are 79% effective in preventing transmission if everyone is wearing one. Another model estimates if 80-90% of the population wore masks when in contact with others, community transmission would be eliminated. Any kind of mask, from a repurposed cotton sock to a surgical mask, is effective. Double-masking with a surgical mask under a cloth mask can double efficacy. 

But there’s not a lot of data about how effective masks are outdoors. One study found less than 10% of all COVID cases were transmitted outdoors — though this hasn’t been tested under the Delta variant, University of Melbourne epidemiologist Tony Blakely tells Crikey. 

“Last year we thought outdoors there was enough natural ventilation, but with Delta it’s just a completely different game,” he said. “Theoretically, it will make a difference. Outside transmission probably wasn’t that consequential last year, but this year it is.”

Smaller bubbles and curfews

Sydney residents can travel only 10 kilometres from their home to shop for essentials and exercise. During Victoria’s 112-day lockdown last year, travel was limited to five kilometres and in South Australia it’s just 2.5km. 

But finding proof these restrictions have a major effect on limiting transmission is tough, Blakley says. 

“In each of the tiered stages of lockdown, we don’t always know exactly what the contribution is of each component,” he said. 

While radiuses limit people from mixing and curfews serve as a reminder of the state of emergency, their efficacy isn’t known. Curfews may also have the opposite effect, causing people to rush to essential stores at the same time before curfew or prompt people to have indoor gatherings instead of going for a late-night walk. 

Limit essential workers

Professor of biostatistics at the University of South Australia Adrian Esterman tells Crikey the government’s broad definition of essential workers was a concern. Workers in retail, education, transport, manufacturing, agriculture and services to maintain and upkeep public and recreational spaces are all deemed essential in NSW. 

“There’s still a huge list of people considered to be essential workers,” he said. “It’s enormous and I would ask whether they really are all essential.” 

Whatever the rules, they must be adhered to 

Whatever the rule, it all comes down to reducing mobility and limiting the number of people in contact with one another. But Sydney residents have not been sticking to the rules: last week, modelling by the University of Sydney estimated just 40% of residents were staying home. If 80% of people complied with public health orders, lockdown would be over in a month, researchers said. But if that number dropped to 70% it would take two months.

The next few days are crucial as the impact of restrictions implemented last week will be known. Esterman is critical of the government’s response, saying NSW should have gone into lockdown a week before it did and is unlikely to curb the outbreak until September. But he says NSW is likely to have hit its peak COIVD-19 cases — as long as people follow the rules.