THE contaminated NHS blood scandal, which left hundreds of Scots infected with deadly viruses such as HIV and hepatitis C, is comparable to major disasters such as Lockerbie and Piper Alpha, according to campaigners.

Around 300 out of 500 Scots who were infected - most of whom were haemophiliac patients - are thought to have died as a result of being given contaminated blood products or transfusions during the 1970s and 1980s.

More detailed figures on the toll will be one of the key findings expected to be included in the final report of the public inquiry into the scandal chaired by Lord Penrose, examining how haemophiliacs and other patients were infected.

The report will finally be unveiled on Wednesday - six years on from the start of the inquiry, which took place over 89 days and involved 60 witnesses.

Campaigners are now calling for swift action to be taken following the publication of the Penrose Inquiry report, including the setting up of Scottish compensation scheme - similar to payouts which were made to affected patients in Ireland.

After decades of fighting for justice, they have called for the Scottish Government to implement any inquiry recommendations by April next year.

Bill Wright, chair of charity Haemophilia Scotland, said the scale of the scandal was comparable to disasters such as Lockerbie and Piper Alpha.

"That is not to belittle those disasters, but it is important to put this into context, in terms of the numbers that have died and have been made very ill," he said.

"The difference with this disaster is that this happened over several years, right across Scotland and Britain, rather than a single time in a single location.

"Unfortunately it continues right up until this day - there are still people who are very ill as a consequence and there are still families living with the grief."

He added: "We will have to wait and see what the Penrose Inquiry report says, but we think there have been around 500 infected in Scotland and as many as 300 of those could be dead. It is important to remember behind every statistic there is a real life."

The findings of the report - which is expected to be published in as many as five volumes - will be released at a press conference in Edinburgh on Wednesday.

On Friday it was announced that Lord Penrose would be unable to attend as he is being treated in hospital for a serious illness. His statement on the inquiry's findings and recommendations will instead be read by Inquiry Secretary Maria McCann.

A number of interested parties have already been given an advance copy of the report to allow them to digest the findings, with strict instructions not to discuss it before the official unveiling of the report.

However the fact that it took nearly a year to issue warning letters, which are sent to those who may be the subject of significant or explicit criticism in the report, has raised speculation that several individuals could be condemned for their actions.

Thousands of patients across the UK, mostly haemophilia sufferers, contracted HIV and Hepatitis C through contaminated NHS blood and blood products,

Key issues which victims have repeatedly called to be scrutinised include: the standards of production of blood products and whether the infections could have been prevented - with major issues such as blood being sourced from US prisoners and not being properly screened.

Many of those who were infected with HIV did not find out until years after that they had contracted the virus, and some patients said they were used as "guinea-pigs" for early research into the virus without being told they had been infected.

Wright, who spoke to the Sunday Herald before any copies of the report had been released, said a major concern was any recommendations would be implemented swiftly. Wright contracted Hep C through contaminated blood.

He said there had been a failure to implement a series of measures around compensation and support services in 2002, which had been recommended by an expert group set up by the then Scottish Government and headed by Lord Ross.

Some no-fault government payment schemes have been set up over the years to provide support for victims. However with an average payment of between £20,000 to £60,000 these have been criticised as falling far behind examples in other countries such as the Irish scheme, which offered average payouts of around £300,000.

Wright said: "We are proposing that action is taken by World Haemophilia Day - which is April 2016. That is a very ambitious target for government to take action, but we believe it is achievable and we believe that if governments want to signal us that they mean business then they will try and meet the target.

"That will be for example, to look at the financial losses that people have experienced and for some sort of scheme to be drawn up that can actually meet those financial losses."

Wright said other key issues campaigners wanted to see addressed included lessons to be learned from the scandal and for more support to be put in place for victims.

He added: "What we are looking for is justice and truth and an apology. I think a lot of people would feel more able to deal with the situation if there was an acknowledgement in the form of some sort of apology about what they have been through. The final thing is we don't want to see any repeat of this (disaster)."

The Penrose inquiry was instigated by the Scottish Government following a pledge made by the SNP in their 2007 election manifesto.

A Scottish Government spokesman said: "The Scottish Government will make a full response to the findings of the Penrose Inquiry as soon as possible following publication, giving full consideration to any recommendations contained in the report."