Virus experts split on mask rule as city lockdown ends
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A leading epidemiologist has labelled the state government's move to keep masks mandatory outdoors a "burden" on Melburnians with very little health evidence.
Melbourne's lockdown will be lifted as planned on Friday, but health experts have reneged on their proposal to scrap outdoor mask wearing, despite admitting coronavirus had not been transmitted outside in any recent outbreak.
It comes as authorities scramble to work out how a family of four mysteriously caught the virus.
A woman in her 70s and three men, in their 80s, 50s and 20s, from the same Reservoir home, tested positive on Wednesday. None have visited an exposure site or been identified as a close contact of a positive case, and their strain is unknown.
One of the family members is a recipient of a disability pension, while another provides care in an informal setting.
Deputy Chief Health Officer Allen Cheng said: "These new cases are really the strongest reminder that we are no means out of the woods yet."
But health officials deemed the "cautious" easing of Melbourne's restrictions - allowing schools to reopen, restaurants to have 100 patrons, only 50 indoors and travel up to 25km - could go ahead.
"We are moving ahead but we are on high alert," Acting Premier James Merlino said.
Questions have been raised as to the effectiveness of wearing masks outdoors, after both Professor Cheng and COVID-19 commander Jeroen Weimar confirmed no cases in the current cluster or recent outbreaks had been acquired while outside.
"We have no evidence that we've seen yet in this particular outbreak, or the most recent ones we've dealt with, of outdoor transmission," Mr Weimar admitted on Thursday.
Professor Cheng said there was "pretty good evidence" around masks reducing transmission, and that cases where the virus was passed outdoors in the second wave might have gone unnoticed.
When asked about reports that transmission was 20 times less likely to happen outdoors, Prof Cheng said: "That doesn't mean zero. There is still a risk."
Infectious diseases expert Prof Peter Collignon said little to no transmission occurred outdoors, unless in crowded situations where people gathered for prolonged periods.
"Unless you've got uncontrollable spread like in the UK or Europe, I can't really see it'll provide much benefit to wear masks outdoors," Prof Collignon said. "There can't be much community transmission in Melbourne right now, if any."
Mr Merlino said the continued wearing of masks was a "small price to pay".
"We don't have the luxury of picking and choosing public health advice that we like or don't like," he said.
Victoria Police Chief Commissioner Shane Patton revealed on Thursday about 50 people were fined $4500 for "blatant" breaches during the recent lockdown.
Meanwhile, Queensland authorities confirmed a Melton couple who tested positive for coronavirus did not have an exemption to enter the state, but are believed to have been moving their for work.
The couple, both in their 40s, left Melbourne on June 1 and travelled through NSW, before arriving on the Sunshine Coast on June 5.
They first became symptomatic on June 3, but Victorian contact tracers have little information on the case given they are now in the hands of Queensland authorities.
Prof Cheng flagged the new cases could stall the planned easing of restrictions in greater Melbourne from Thursday June 17.
"We may need to hold on the current settings for a little longer," Prof Cheng said.
CALL FOR SCHOOLS TO OPEN DURING OUTBREAKS
Pressure is mounting on schools to stay open during Covid-19 outbreaks, as 200,000 Victorian children return to class today after their fourth gruelling lockdown.
An internationally-regarded panel of infectious diseases experts and paediatricians has found closures should be a last resort because of low student transmission rates and the negative effect on children.
They recommend all Australian states and territories "institute a national strategy and commitment to keeping schools open", with systems and funding to measure the policy's effectiveness.
"Teachers and school staff should also be prioritised for Covid vaccines, especially in settings with higher incidence of Covid-19. Our kids depend on it," lead author Dr Archana Koirala, of the University of Sydney, said. The global analysis, published in the Journal of Paediatrics and Child Health, included 1635 Victorian infections in schools and early learning settings from 2020.
They found two-thirds of Covid-19 outbreaks involving Victorian schools were single cases with limited transmission, and 92 per cent included fewer than 10 cases.
One of the researchers, Professor Sharon Goldfeld from the Murdoch Children's Research Institute, said closing schools "should be a last resort, especially for childcare and primary school children as cases in this age group are less likely to transmit and be associated with an outbreak".
From almost one million Victorian school students, 337 students and 139 staff may have acquired Covid-19 via a school outbreak last year.
Of these, four staff and four students went to hospital and all recovered.
The researchers found little evidence of onwards transmission of cases from school and early learning centres, particularly among younger children.
Victorian children have lost as much as 23-and-a-half weeks of school in the past two years, compared with seven weeks in NSW, five weeks in Queensland and just one week in South Australia and the NT.
But Education Minister James Merlino defended the closures on Thursday, saying that "schools play a critical role in restricting the movement of Victorians and therefore the spread of the virus".
Dr Koirala and her team concluded that data from Victoria, NSW and WA showed that "transmission within school settings is low and can be mitigated through Covid-19 safe practices and effective measures to test, contact trace and isolate".
Originally published as Virus experts split on mask rule as city lockdown ends