The Hepatitis C blood contamination scandal has cost the State over €1.5bn, according to the Annual Report of the Comptroller and Auditor General.

It also found that towards the end of last year, the HSE was forced to limit the patients offered treatment for budgetary reasons.

Around 1,700 people were infected with the disease - mainly between the 1970s and the 1990s - following exposure to contaminated blood and blood products.

€1.17bn was paid out in compensation, and ancillary legal and administrative costs - with the remainder accounted for by medical services provided free to patients.

According to the report, the HSE estimates that up to 30,000 people have been infected with Hepatitis C - many through intravenous drug use. A course of treatment can cost up to €92,000.

The report notes that since 2017, about 98% of patients who chose to accept treatment had a successful outcome.

The C&AG report said the HSE considered that significant progress had been made in providing treatment for Hepatitis C as a result of the development of a national treatment programme in 2015 - and that all those infected by blood and blood products had been offered treatment by the end of 2017.

The report says that the total net spend on the Hepatitis C treatment programme was around €30m in 2017. It says 1,072 patients commenced treatment at an average net cost of around €28,000.

The HSE had forecast that by the end of July, it would have used 60% of the net budget available, but instead, by then most of the budget had been used - forcing the HSE to suspend the programme until it could determine how many patients the remaining budget could support to commence treatment up to the end of 2017.

Even when treatment centres were told they could re-commence treatment, clinicians were instructed they could only select patients with the "genome 1" type of disease.

According to the C&AG, the HSE justified this decision saying it was intended " support clinicians in having access to some treatment until such time as an updated financial position was available".

In October of last year, the treatment centres were told they could select patients based on those in "most critical need" - and these measures continued to the end of 2017 to ensure that the programme operated within budget for the year.

In 2002, the Hepatitis C compensation scheme was extended to encompass patients who contracted the HIV virus, also through blood products.