Scabies cases at the Alexander Maconachie Centre have almost tripled within a week.
Seventeen cases of scabies were identified as of Wednesday, a significant increase from the four detainees initially diagnosed with the highly contagious skin disease last week.
ACT Chief Health Officer Paul Kelly said a public health intervention to manage the outbreak has been launched.
Scabies is caused by a microscopic mite. The infestation causes people to break out in rashes but is easily treatable with a topical cream.
The average daily number of people in full time custody in the ACT was 278, according to June quarter figures issued by the Australian Bureau of Statistics yesterday.
The release stated that of all the state and territories, the ACT had the highest proportion of prisoners in secure custody at 96 per cent while the territory had the highest proportion of inmates waiting to be sentenced at 34 per cent.
The ACT also recorded the lowest imprisonment rate in the country, at 96 prisoners per 100,000 adult population.