A Canberra repatriation flight passenger could be made to stay in hotel quarantine for longer if she returns a second positive test for COVID-19.
ACT Chief Health Officer Dr Kerryn Coleman said on Monday the woman in her 30s had returned a "very, very low" positive reading for the virus during exit testing from hotel quarantine.
She said authorities were confident the woman had tested positive because of an old and inactive infection.
Dr Coleman said the woman, along with other passengers on the ACT's most recent repatriation flight from Chennai in India, was due to be released from quarantine first thing on Tuesday morning.
But the ACT government confirmed on Monday afternoon the woman would undergo more testing before she was released.
"There is no risk to hotel and government staff from this recovered case," a spokesperson said.
"As a precaution, however, further tests will be done today before the individual is released from hotel quarantine."
Pacific Suites on Northbourne Avenue is currently the only place where hotel quarantine is happening and can happen in Canberra.
Dr Coleman said the woman had tested positive to coronavirus back in December, before she arrived in Canberra on February 8, and had tested negative on her entry to hotel quarantine.
"We do know that people who have previously been infected can still shed intermittently the virus and that's what gives us sometimes that positive sewage result that we see," she said.
The government spokesperson reiterated that point.
"The weak positive test result from yesterday is almost certainly due to her known previous overseas-acquired infection, and reflects prolonged shedding of virus fragments," they said.
"This is known to happen intermittently for up to several months after a person is no longer infectious."
Dr Coleman attended the Garran Surge Centre on Monday morning to witness the ACT's first COVID-19 jab.
She said the woman's positive test was based on only a couple of genetic locations and, if authorities had "any doubts at all", the woman would not be released from quarantine come Tuesday morning.
The government spokesperson said: "As this case has been previously reported and managed as a case overseas, it will not be formally counted in the ACT or Australia's total infection numbers."
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