Health Service in the 1970s and 80s. Many have since died. Others unknowingly passed infections onto partners who then died. Victims and their families have spent decades fighting for compensation. Chloe Hayward explains.

It's known as the biggest treatment disaster in NHS history and so far we know that 3,000 people have died in the UK from infected blood and infected blood products they were given by the NHS. Overall, 30,000 victims have been identified.

And these fall into two main categories. There's the people with rare genetic blood clotting disorders such as the haemophiliacs and there's people who needed blood transfusions after surgery for example. So let's start with this first group, the haemophiliacs. So people with blood clotting disorders, they need a special protein called Factor 8 or Factor 9 injected which helps their blood clot. But by the 1970s, the UK was really struggling to meet demand for these blood products and so they started to import from America.

But because America pays for blood plasma rather than it being donated for free, it came from a lot of high risk individuals including prisoners, drug addicts and those most in need for money. And so with these donations came some deadly viral infections such as Hepatitis C and HIV. In the late 70s, US drug companies were aware that their product was infected with viruses including Hepatitis but they didn't take steps to stop that transmission. Instead what they did is they mixed together ever larger batch numbers of donations, sometimes up to 50,000 plasma donations would be mixed together in one batch and it took just one infected donor to infect the entire batch.

By 1983, the pharmaceutical companies, they were aware there was a link between haemophiliacs and HIV but instead of raising the alarm, they kept it quiet.

Some medics and whistleblowers did try to raise the alarm around the world but health officials did not listen. We now know that 1,250 people were infected with HIV and Hepatitis C who had blood clotting disorders in this country. 320 of them were children and almost all have now died. Now let's look at this second group of people, those with blood transfusions. They were given blood transfusions during surgery or after childbirth or an accident and they were given it, it was infected with Hepatitis C.

It was known that blood transfusions could infect people with Hepatitis as early as the 1970s but those that it exposed, they weren't tested even when a test became available.

A minimal effort was made to identify those infected. Even now we still have people coming forward in this country who have just been diagnosed decades after their infection but often it's too late. You see Hepatitis attacks the liver leading to cirrhosis and eventually cancer so a late diagnosis often comes with a dire prognosis.

The inquiry said that through blood transfusion treatment up to 27,000 people were infected with Hepatitis C and between 80 and 100 got HIV.

During the inquiry we heard from children that grew up as orphans, mothers who buried their children and husbands who unknowingly passed infections onto their wives. Victims said they were ignored by doctors and they said they were treated as dirty or second class citizens by the NHS. Victims and their families have waited 40 years for justice.

The focus now is on compensation.

That was Chloe Haywood reporting. Let's speak now to our news correspondent Rajini Vaidyanathan who is outside the Methodist Central Hall in Westminster. Hello to you Rajini. A huge day for all the families and people who've been affected by the infected blood scandal.

Just tell us where you are now, what the atmosphere is like where you are now and what people are hoping, what they're expecting.

Well family members have been arriving here. They are going to be getting a copy of the report and at 12.30 today that will be made public, the findings of an inquiry which has lasted some four years and to so many relatives and people who are surviving through this scandal. It's been a long time coming and I think there are three things that people really want today, the family members and the campaigners. It's a refrain that we hear in other public inquiries, they want truth, they want justice and they want accountability.

Let's start with the first one, truth. They just want to know what exactly happened, how could it have been that so many people, thousands as we heard from Chloe just then, were treated using a blood product which was infected with HIV and with Hepatitis C. Hundreds of children ended up dying too soon as a consequence, thousands of people have died and we heard from the Labour MP Diana Johnson who's been a campaigner for this who says that it's estimated that every three to four days somebody dies as a consequence of what happened decades ago. So it's truth, it's also justice as well. They want people to know that they want not just compensation, it's not just about money for people, but it's also knowing that they were right all along. So many families, Sarah, say that they felt they were gaslit.

There were warnings at the time, even as early as the end of 1983, that this product that was coming over, this Factor VIII from America, was infected with HIV and Hepatitis C but those warnings were not heeded and so it was continued to be used, it was seen in some ways as a wonder drug, a product that could really help treat haemophilia, particularly in children, in a more efficient way. And then the last one is accountability because

I'm speaking to you not too far from Downing Street, from the House of Commons and the

Ministry of Health and people want to know who's going to be held accountable for this.

Now in many ways this goes beyond politics because this scandal has happened through successive governments, different political parties in charge. But in a way, the buck does stop with the current government, some people say. They want to know whether there might be an apology even later today. We are expecting perhaps to hear from the Prime Minister once the report's findings are released. Will he apologise? Who knows.

Regine, we will be crossing back to you throughout the day as this hugely important report is published. But for the moment, thank you.