Queensland has reported nine new cases of community-transmitted coronavirus.
Deputy Premier Steven Miles told reporters on Sunday a cluster in Brisbane's suburb of Indooroopilly now stands at 18 after a recording 6 cases on Saturday.
“This is the most number of new community infections we have reported in Queensland in almost 12 months," he said.
The new cases include a Brisbane Boys Grammar student who attended a karate class at Ironside State School and his dad. Two more are linked to Ironside and two to Indooroopilly State High School.
All 18 in the Indooroopilly cluster are the highly infectious Delta strain of coronavirus.
Brisbane City along with 10 other LGAs remain in lockdown which started at 4pm on Saturday and is expected to be lifted on Tuesday at 4pm.
The 11 LGAs are now considered national hotspots.
Search to find the missing Covid link
Queensland Chief Health Officer Dr Jeannette Young said health authorities still do not know how the cluster started.
However, Dr Young suspects the outbreak might have started on the Sunshine Coast.
"I still think there will be cases there in the Sunshine Coast that we don't know about and if we don't find them, they will continue to spread," Dr Young said.
The current cluster first came to light after an Indooroopilly State High School student tested positive for coronavirus on Thursday night.
Dr Young said the student, aged 17, has the same genomic sequence as two overseas travellers. One of the travellers came from Indonesia and another from the UK.
She believes somehow it was transmitted from a person discharged from the Sunshine Coast University Hospital on July 17.
“This is why I asking that anybody in the Sunshine Coast who is unwell with any symptoms at all to immediately come forward," she said.
The deputy premier echoed her statement.
"We did 11,468 tests in the last 24 hours," he said.
"Our message is simple. That is not enough tests. We need more Queenslanders, particularly in the southeast to get tested."
More to come.
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