Queensland is now fighting two COVID-19 clusters sparked by an unvaccinated doctor and nurse who worked with coronavirus patients from overseas at the same Brisbane hospital.
A female doctor from Princess Alexandra Hospital is believed linked to cluster one, and a female nurse at the same facility is assumed central to cluster two.
Both clusters are circulating the highly transmissible UK strain, also known as B1.1.7.
Here's what we know about each cluster.
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Cluster 1 – Eight people, with two under investigation
The first cluster is related to a doctor at the Princess Alexandra Hospital who treated a confirmed case, Chief Health Officer Jeannette Young said.
The infected patient had earlier passed the virus on to another returned traveller while they were in hotel quarantine.
So by March 12, there were three cases in this cluster.
Later, two men who live in northern Brisbane came forward and returned positive tests, bringing the cluster to five.
Three more cases were then added to the cluster.
Two further cases are currently under investigation, which Dr Young expects will be confirmed as linked to cluster 1 soon.
So, cluster one totals eight people, and is likely to move to at least 10.
Cluster 2 – Eight people
The nurse at the centre of this cluster worked at Princess Alexandra Hospital on March 18, in the COVID ward.
However, genomic testing has linked her to a patient, a returned traveller, who was only admitted to the hospital on March 22.
After her 18 March shift, Dr Young said the nurse's next shift was 23 March, with that shift beginning at 10pm.
That night she worked through into the next day, on the 24th.
Queensland Health are trying to establish how the nurse caught the virus, whether directly from the returned traveller or another means of transmission.
The nurse passed the virus to her sister, and the pair were part of a hen's party that travelled to Byron Bay, in the north of New South Wales.
Today, it was confirmed another five people on that hen's party had tested positive, including a tradie who was with the group as an "entertainer".
That tradie, who lives on the Gold Coast, worked at a Queensland aged care facility after returning from his "entertainer" work on the Byron trip.
Residents at that aged care facility have been given their first vaccination jab, Queensland Health said.
It was not known yet if any vulnerable residents had been administered a second dose.
So, including the original returned traveller, cluster two totals eight people.
Dr Young said, separate to the above, that one outstanding case under investigation could be linked to either of the clusters.
READ MORE: NSW expects new cases after Byron Bay hen's party
