There is growing concern Queensland is heading for a snap lockdown after a new mystery coronavirus case in the state's south-east.
Authorities are on the verge of announcing a three-day lockdown later today, 9News understands.
A testing blitz has begun after hundreds of students and staff from Brisbane's Indooroopilly State High School were sent into isolation due to a student testing positive.
READ MORE: Brisbane school with COVID-positive student listed as close contact exposure site
The school in the city's west, has been locked down for deep cleaning after the 17-year-old female student's test came back positive late on Thursday.
The school was yesterday named a close contact exposure site, meaning anyone who was there from 8am to 10am on Tuesday or 8am to 3.30pm on Wednesday must immediately quarantine at home and get tested.
The school has more than 2400 students.
The student had attended school for the past two days before becoming unwell yesterday.
Authorities are at a loss to explain how the teen contracted the virus.
READ MORE: The highly contagious Delta strain explained
Health Minister Yvette D'Ath said her family of five have been tested.
"She's been in the community for three days and at school for two days, so I understand the school has already notified families and have closed down for a deep clean."
Chief Health Officer Dr Jeanette Young said the teen came forward for testing after having a headache, but how she caught COVID-19 remains a mystery.
"We'll have to wait until we get whole genome sequencing results back later today to work out from where she's got this," Dr Young said.
The girl had been in the community for three days from July 27 and at school for two days.
