No jail workers have been infected with COVID because of the current outbreak, the Justice and Community Safety Directorate says.
Of 383 inmates at the Alexander Maconochie Centre, 30 had the virus on Tuesday at 3pm.
While 19 prison staff members have been impacted by COVID-19, the directorate said none were known to have been infected as a result of the current outbreak.
There is a very high vaccination rate among correctional services workers, Community and Public Sector Union regional secretary Maddy Northam said.
The justice directorate said it was aware of a positive case at the jail on Saturday and the man was immediately put into isolation.
"As a precaution, AMC initiated a restriction on movements between accommodation areas on Sunday," a spokesperson previously told The Canberra Times.
"All detainees accommodated in the impacted male area of the AMC undertook a PCR test."
In-person family visits have been stopped until May 18 but the directorate says inmates have access to phones and computers in their accommodation areas.
"AMC is well placed to enable legal and welfare engagement strategies as was practiced during mandatory lockdowns," a spokesperson said.
It is understood inmates have accessed legal aid services over phone or computer since the COVID pandemic started and despite the current outbreak it is business as usual.
It is also believed detainees are unable to access in-person welfare visits.
Ms Northam from the public sector union said managing movement of prisoners within the outbreak was a tough job.
"Correctional officers are doing a great job in a very tough environment," she said.
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