An action plan drawn up to tackle the growing threat posed by hepatitis C in Wales is three years behind schedule, according to a group of MPs.
A parliamentary report claims the Welsh Assembly Government has drafted the plan, originally due in 2006, but has failed to publish it.
The Hepatitis C Trust accused ministers in Wales of "ignoring" sufferers.
The assembly government said Health Minister Edwina Hart was expected to publish the plan shortly.
Hepatitis is an inflammation of the liver and hepatitis C is one of several viruses that can causes the illness.
Research from the University of Southampton estimates there are as many as 466,000 infected people in the UK, with 12,000 in Wales.
But the all party parliamentary hepatology group said there were "vastly inconsistent approaches in how hepatitis C is being tackled across the UK".
Its report shows Scotland is leading England and Wales in its response to the public health challenge and it has drawn up a two-phase action plan.
However, the Blood Borne Viral Hepatitis Action Plan for Wales, tackling both hepatitis B and C, has been drafted but not published or put out for consultation, said the MPs.
"Our report shows there's so much more that needs to be done to tackle hepatitis C in England and Wales," said Bob Laxton MP, co-chair of the all party parliamentary hepatology group.
"Scotland is leading the way and we must quickly follow otherwise we will continue to see more and more unnecessary deaths from hepatitis C."
Charles Gore, chief executive of The Hepatitis C Trust, said the assembly government could not be allowed to continue postponing publication of its action plan any longer.
"Years have gone by with very little progress while the death toll just keeps growing - why are patients in Wales being ignored?" he added.
The assembly government said it was committed to meeting the challenge of blood-borne viral hepatitis.
A spokesman said: "A significant amount of work has been undertaken in the development of an action plan.
"A draft plan, prepared by the National Public Health Service (NPHS), was submitted to assembly government officials for consideration.
"The process for setting budget allocations for 2009-10 and beyond is currently underway and the costs and timetable for implementing the plan is being considered in that process."
There is no vaccine to protect against hepatitis C, which is usually transmitted through blood-to-blood contact, but there is effective treatment available.
According to the MPs' report, if left undiagnosed and untreated, the future burden of hepatitis C on the NHS in the UK could reach up to £8bn during the next 30 years.