A man in Collie, south of Perth, has tested positive for COVID-19.
The Health Department says the man recorded a very weak positive result which likely reflects a historical infection.
The man, in his 30s, travelled to Australia from Poland via Victoria, where he underwent 14 days of quarantine at a Melbourne hotel.
He then travelled to WA.
The WA Health Department said the man tested negative to COVID-19 on all his tests while in hotel quarantine.
"On his return to Collie, he was re-tested as part of Vic Health’s follow-up of people post-quarantine," the statement said.
"He returned a very weak positive result, which is sometimes seen in people with old, recovered infections.
"WA Health believes the test result most likely reflects an historic infection but out of an abundance of caution has re-tested the man to clarify his infection status."
The man and three of his close contacts have been ordered to isolate and he will be re-tested.
The results of these tests, which will include antibody tests, are expected back tomorrow.
"We are asking the community not to panic and to be assured that WA Health will advise the community if results indicate this is an infectious case," the statement said.
Shire president Sarah Stanley said the man had caught up with her and other friends at a pub on his return to Collie.Collie Shire president Sarah Stanley has put herself into self-quarantine after having contact with the man at the local pub, the ABC understands.(
"He has been out and about seeing a few of his friends, including us and then has since returned a post-quarantine test as positive," she said.
She said those who had been in contact with the man had put themselves into quarantine.
"He was pretty proactive and just contacted all the people that he knew he had caught up with during that time," she said.
"Those people have started to take their own steps ahead of the health advice.
"It's still very very early days.
"The contract tracing team is doing what they do and working out who they need to contact and what advice they need to give."
WA Health's director of communicable disease control, Paul Armstrong, said he hoped further testing would reveal the patient as a "non-case".
"We think that he's just shedding at the moment and that means he's not infectious," he said.
"It's looking more and more likely that this is a historical case and therefore would not be a risk to the public"
Dr Armstrong said the man did not pose a risk to public health.
"Business should be as normal, there's no need to deep clean, there's no need for people to isolate themselves," he said.
"Our feeling at the moment is that this is highly unlikely to be a true case."
Results from the man's most recent tests will come back on Wednesday morning.
Australian Medical Association (AMA) president Dr Omar Khorshid told ABC Radio Perth that while he was yet to be briefed on the details, he assumed authorities must have a reason to suspect the case was a historical one.
"If this chap tested negative in quarantine in Victoria and is now testing positive, then that does raise the question of whether it's a new case," he said.
"But I can only assume that the authorities have got a reason to suspect it's a historic case based on this individual's history and maybe he or she has had the virus in the past."
Health Minister Roger Cook told state parliament he was made aware of the case on Tuesday afternoon.
"At this stage, I would just like to stress that it is a weak positive and from that point of view we don't hold grave concern in relation to this outcome, but we are taking a precautious approach," Mr Cook told parliament.
"He will be tested again to determine whether he is in fact a positive, or what is called a historical case.
"Our strong suspicion at this stage is that he is an historic case, which means that he is shedding particles of the virus, and that can from time to time trigger a positive result in the usual testing process.WA Health Minister Roger Cook says authorities do not hold grave concerns about the case.(
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"So, we will test him again. He is isolating, all his close contacts are isolating until we get a clearer signal in terms of his test outcomes.
"We will determine this through a serology test, which tests for antibodies which is really the defining characteristic that we would see in somebody who is considered a historic case."
Mr Cook said the Health Department was liaising with the man's employer.
Posted 5hhours ago TueTuesday 4 MayMay 2021 at 6:02am , updated 3hhours ago TueTuesday 4 MayMay 2021 at 8:18am