Random COVID testing will be conducted again this weekend as Queensland health authorities seek to better understand the extent of coronavirus ahead of another potential wave in winter.
The results of a maiden survey project on the Gold Coast revealed yesterday that up to one in six residents have been living with COVID during the peak of the virus in the region.
The survey randomly conducted PCR tests on 117 people on January 22, with 20 testing positive.
Only four of those people reported having any symptoms and only two were aware they had the virus, meaning 90 per cent were unaware they were infected.
A follow-up survey, a week later, performed on 143 random Gold Coast people saw 11 test positive, with six of those reporting symptoms.
Most people in the study with mild or no symptoms were fully vaccinated.
COVID more prevalent than we think
Chief Health Officer John Gerrard said the results showed coronavirus was much more prevalent in the state than test results demonstrated.
"At this stage we still don't know exactly the total number of people… in Queensland that have been infected with the virus," Dr Gerrard said.
Queensland Health has confirmed another round of random tests will be conducted this Saturday on the Gold Coast.
Further random studies may also be conducted across the state, depending on the results of the Gold Coast tests and prevalence of cases.
Any data collected will be aggregated nationally to inform COVID procedures going forward.
"We are trying to work out how many, what proportion of the population has actually been affected and what degree of immunity that has created," Dr Gerrard said.
So why aren't I feeling symptoms?
University of Queensland virologist Kirsty Short said the severity of a virus's symptoms could be influenced by "host factors".
In the case of COVID, Dr Short said those include vaccination, age and "underlying metabolic conditions such as obesity and diabetes".
"We know vaccinated people can get infected… but they may be asymptomatic," she said.
"If you're generally not healthy… if it's malnutrition, underlying conditions… there's something going on, we know that that can make the virus worse and make you more likely to be symptomatic.
"The sort of take-home message is that the best thing that you can do to keep yourself healthy is, first of all get vaccinated, but also just watch your general health."
Dr Short said the results of the survey weren't surprising and the amount of unknowingly infectious people in the community reinforced the need to take precautions, such as wearing masks and socially distancing.
New variants may arrive by winter
The state is planning for further waves of the pandemic, with winter flagged as a key concern.
Dr Short said new variants of COVID were also "very, very likely", especially if a large population globally did not have access to the vaccination.
Dr Short said the amount of Omicron cases with mild or no symptoms in Queensland was a positive sign.
"We're still seeing that vaccine is very, very effective in terms of preventing severe disease," Dr Short said.
"That's really reassuring that if [further waves] do happen, then maybe we'll have infections in the community, but they'll be largely asymptomatic and not causing severe disease."
