Queensland Health contract tracers are once again in overdrive after the state recorded two community cases of COVID-19.
A 26-year-old landscaper tested positive for the virus late Thursday night, and on Saturday it was announced that a close contact of the man has also been diagnosed.
Genomic sequencing linked the landscaper's case to that of a Princess Alexandra hospital doctor who was diagnosed on March 12.
However, with no apparent contact between the pair, the source of the man's infection remains a mystery.
Here's what we know so far.
The new cases.
The landscaper is currently being treated in isolation in hospital for the more-infectious UK variant of COVID-19.
He began to develop symptoms on Monday and remained home before testing positive on Thursday.
His infection has been tied to that of the Princess Alexandra hospital doctor who had contracted the virus from returned travellers earlier this month, ending the state's two-month streak of no community transmission.
The doctor had visited four venues in Brisbane's south while infectious.
However, on Friday, Queensland Chief Health Officer Jeannette Young said it was likely the new case had caught the virus from an intermediary who is yet to be identified.
We must get back into the habit of social distancing and washing our hands.— Annastacia Palaszczuk (@AnnastaciaMP) March 26, 2021
Stay home if you are sick and get tested.
These basic things kept us safe all through last year – and they can again.
Stay safe, Queensland.
There are limited details available about the second case, but it's understood the man is a friend of the landscaper.
Queensland Premier Annastacia Palaszczuk said he is working with the state's Public Health Unit to assist in contact tracing.