The number of inmates at Canberra's adult jail with Hepatitis C has fallen more than 20 per cent in the past seven years.
But community health advocates have urged the territory to keep its eye on prevention as well as treatment.
Justice Minister Shane Rattenbury on Friday released new figures showing how new drugs for the virus had helped reduce the number of Hepatitis C-positive inmates from 30% of the prison population in 2010 down to just three per cent this year.
He said in the year to March 2017, another 58 detainees had also started the expensive treatments, which were approved by the Pharmaceutical Benefits Scheme last year.
Mr Rattenbury's announcement of the figures came on World Hepatitis Day on Friday - a World Health Organisation-endorsed day - this year aimed at outright elimination of the various strains of the virus.
Hepatitis ACT manager John Didlick backed the progress already made at the prison, and the government's "tremendous" $5 million investment in the new treatments being delivered in the Alexander Maconochie Centre.
"The whole community should be delighted with the progress made by Justice Health in treating so many people," he said.
"But given the extent of in-prison transmission of Hepatitis C, that tremendous investment in public health needs to be hedged with a comprehensive suite of evidence-based prevention strategies," he said.
Mr Didlick again urged more be done to prevent the transmission of the virus - particularly on the "basics" of "awareness, testing, treatment and vaccination for Hepatitis B" as well as regulated needle and syringe programs.
"Without all the legs on a chair, it tends to fall over," he said.
But the proposal for a syringe program inside the prison has been held back for years with deeply divided opinions - with the health sector largely supportive, but the prison officers' union opposed.
The idea was also previously backed by the ACT Government, before it cast the proposal aside ahead of last year's election campaign.
But Melanie Walker, chief executive of the Australian Injecting and Illicit Drug Users League, urged it be re-considered alongside wider prevention strategies.
"We need the full suite of evidence-based approaches if we are to overcome this key public health challenge in Australia," she said.
The headway made in the AMC reflects a wider trend across Australia since the new direct-acting antivirals were approved in March 2016.
A report from the Kirby Institute released last week showed that of the 230,000 Australians estimated to be living with Hepatitis C, some 38,470 people had begun the therapy since it was approved.
That was a more than ten-fold rise on the 3000-odd Australians being treated on average each year before the new treatment was approved.
The Institute's Professor Greg Dore said one of the most exciting developments identified in the research was general practitioner's prescribing the treatments more - rising from only eight per cent before it was listed on the PBS to 31 per cent in the year since.
He said the rise in GP prescribing would help to reach more diverse patients, but that "broader access is vital" if Australia was to eliminate hepatitis C in Australia by 2026, as is the current national target.