As NSW's Covid crisis enters unprecedented territory, the state's chief health officer continues to reiterate the importance of vaccinating the eligible population as quickly as possible.
But with nearly a third of infections in August being detected in children, Dr Kerry Chant is now targeting a new demographic regularly neglected throughout the pandemic.
"I firmly believe that we need to get in and vaccinate our 12 to 15-year-olds at the moment," Dr Kerry Chant said earlier this week, saying it needs to be done "very quickly".
"We know they contribute to transmission."
NSW government data shows that since June 29, three days after Sydney entered lockdown, to Tuesday, there have been 2,728 cases in those 19 or younger, which equates to 30 per cent of all cases in that time period.
On Thursday, Prime Minister Scott Morrison announced those aged above 16 would be eligible for Pfizer from August 30.
But for those aged 12 to 15, the Australian Technical Advisory Group on Immunisation (ATAGI) at this stage has approved Pfizer for Aboriginal and Torres Strait Islander children aged 12–15 years or those with medical conditions that increase their risk of severe Covid-19.
ATAGI said at the beginning of August a decision on all 12-15-year-olds would be made in the "coming months".
Mr Morrison said on Thursday a decision was "imminent".
"Before we move to a mass scale vaccination of children between 12 and 15, we will take that ATAGI advice," he said.
"I think it is important it happens this year."
Children playing a key role in Delta outbreaks
Professor Jaya Dantas from Curtin University's School of Population Health told Yahoo News Australia it was evident children were now playing a key role in Delta outbreaks.
"Currently it's the younger people and very young children who are getting infected and I've said it again and again, we have to see what's happening in the real world and in real time," she said.
Prof Dantas said other nations such as the US have vaccinated over 40 per cent of their children aged 12 to 15, and Australia must follow suit and ensure they are not left behind.
However she said it ultimately came down to supply, and advice on the age group has been delayed thanks to Australia being behind throughout the vaccine rollout.
"It's a huge problem," Prof Dantas said.
The majority of Australia's 40 million Pfizer jabs will begin to arrive from October, however NSW was given a much-needed boost with more than 500,000 vaccines which were acquired from Poland. They will be used in 16 to 39-year-olds in Sydney's local government areas of concern.
Premier Gladys Berejiklian highlighted that age group as the one driving Sydney's outbreak, with workplace transmission fuelling infection.
But with exponential growth in NSW, Prof Dantas said those aged 12 to 15 are now as important as under 30s in curbing the spread.
"We need to roll it out sooner rather than later," she said.
Rowena Bull, a viral immunologist at UNSW, told the ABC children's inability to social distance effectively and a lack of mask wearing, paired with the highly-infectious nature of Delta, transmission was now more frequent in children.
Pfizer approval for children 'should not be rushed'
However Professor Nikolai Petrovsky of Flinders University School of Medicine and Public Health, says a more cautious approach should be taken with approving Pfizer for 12 to 15-year-olds.
He told Yahoo News Australia it must not be forgotten that the main aim for the vaccine is to prevent severe disease.
With severe illness in children remaining extremely low from Covid, Prof Petrovsky says caution is needed due to developmental effects of vaccines "poorly if at all understood and we do not know their long term consequences if any".
"So on a risk-benefit basis such a decision should not be taken lightly and should not be rushed."
Prof Petrovsky said such a move is a presumption Pfizer offers significant reduction of transmission, which current evidence does not show.
However Prof Dantas argued evidence shows transmission from a person who is vaccinated is "much less" than someone who hasn't.
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