HOW BRISBANE'S TWO COVID-19 CLUSTERS SPREAD:
March 12: Brisbane's Princess Alexandra Hospital is placed into lockdown after a doctor tests positive for COVID-19.
March 13: Testing shows a patient from hotel quarantine infected the doctor. All Brisbane hospitals, aged care facilities, disability providers and prisons locked down.
March 14: Authorities investigate whether a COVID-19 case in hotel quarantine at the Grand Chancellor is linked to the doctor.
March 15: Lab analysis shows a Grand Chancellor guest transmitted COVID-19 to another guest in a separate room and later to the PA Hospital doctor between March 5-9.
March 16: Queensland records no new cases of community transmission of COVID-19.
March 19: The lockdown of hospitals, aged care facilities and disability providers and prisons ends.
March 19: The Queensland chief health officer says there won't be another city-wide lockdown in Brisbane if there's a future outbreak.
March 26: A man tests positive in Stafford after being in the community while infectious for a week. His case is genomically linked to the PA doctor case.
March 26: Hospitals, aged care facilities and disability providers and prisons locked down for the second time in a fortnight.
March 27: A Strathpine man, a friend of the Stafford man, tests positive.
March 28: The brother of one of the two men tests positive, but he's not infectious.
March 29: Four new cases emerge in the community, taking the number of cases to seven. The cases include a PA Hospital nurse and her sister, who visited Byron Bay in NSW, and two colleagues of the Strathpine man. Greater Brisbane is ordered into a snap three-day lockdown.
March 30: Eight coronavirus cases reported in Brisbane, with two clusters now totalling 15 cases. Six are close contacts of PA nurse, including a Gold Coast man. Five of those cases also visited Byron Bay in NSW and one of them lives in Hervey Bay. Two cases are still under investigation, but may be genomically linked to the PA doctor.