A Canberra repatriation flight passenger who on Sunday returned a "very low" positive reading for COVID-19 was released from hotel quarantine on Tuesday morning.
ACT Health authorities on Monday said they were confident the woman, who is in her 30s, returned a positive reading during hotel quarantine exit testing because of an old an inactive infection.
They said the woman had COVID-19 while she was overseas in December last year, and tested negative on her entry to hotel quarantine before she ultimately returned a very weak positive result.
"The weak positive test result from [Sunday] is almost certainly due to her known previous overseas-acquired infection, and reflects prolonged shedding of virus fragments," a government spokesperson said on Monday.
"This is known to happen intermittently for up to several months after a person is no longer infectious."
The spokesperson said the woman posed no risk to hotel and government staff, but would undergo further testing on Monday as a precaution before she was released from hotel quarantine.
The ACT government confirmed on Tuesday that the woman had been released, along with the other 165 passengers who were on a repatriation flight from Chennai in India to Canberra on February 8.
It said the woman posed no risk to the Canberra community.
Canberra authorities expect another repatriation flight will touch down in the national capital in March, but it is unclear where the flight will come from and on what day it will land.
Pacific Suites on Northbourne Avenue is currently the only place where hotel quarantine is happening and can happen in Canberra.