Five people have now been confirmed to have contracted coronavirus at the Cairns Hospital pathology laboratory.
Queensland Health is now screening all Cairns Hospital workers for the virus and is urging anyone else in the community who is feeling unwell to get tested.
As Tropic Now exclusively revealed, a laboratory worker tested positive to the virus last week.
Queensland Health has today announced the initial case in the cluster was a laboratory technician who traveled from Brisbane.
A further three people linked to the lab have also had COVID-19 without knowing it, and have since recovered.
Chief Medical Officer Dr Jeannette Young says a new type of test was able to unravel the mystery.
“One month ago a technician went up to Cairns and when he went back to Brisbane he tested positive to COVID-19," she said.
"Initial contract tracing was done in the lab which didn’t confirm anything.
"Then last week we had one of the lab workers, who’s worked in that lab, tested positive and we were unsure where that lab worker actually contracted that infection.
"We now have confirmation that it was in the lab because overnight I received the serology results for three other people who had been in that lab, who had been infected, who had the infection and have recovered.
"But it’s clear that they got it from that initial person and that therefore this latest person got it through that process."
Dr Young said the new test was introduced in Queensland on Monday.
"Only two have tested positive through PCR testing, so acute testing.
"That was the initial case a month ago, who went up from Brisbane…and then the second case was the lab worker last week.
"What we’ve gone and done is a different type of testing, we've done serology testing which looks at immunoglobulin to see whether someone has had the infection, mounted an antibody response and has recovered.
"So we have three people who on serology testing, have tested positive.”
Dr Young said Queensland Health would now focus on preventing "ongoing community spread" in Cairns.
"It’s a cluster that’s occurred so we really need to get on top of it," Dr Young said.
"People in the lab can work in the rest of the hospital, can walk through the rest of the hospital so that’s why today we’re working with all staff members in the hospital to see if anyone else is unwell.
"At this stage we’re just screening all hospital staff to see if they have any symptoms.
"It’s very important that across the whole community in Cairns that anyone who’s unwell with any respiratory symptoms, so cough, sore throat, shortness of breath, that you immediately go and see your own GP or go to the fever clinic that’s there in Cairns to be tested."