Up to 150,000 people in Britain are expected to die over the next 20 years from a treatable disease that most do not know they have.

A silent epidemic of hepatitis C, a blood-borne virus, has infected an estimated 500,000 people in the UK and new cases are rising faster here than in other European countries, specialists said yesterday.

Typical victims of the illness are middle-class professional men and women who dabbled in drugs in their youth and contracted the infection through sharing needles. Other people became infected through contaminated blood transfusions before testing for hepatitis C was introduced in 1991.

The disease is already the main reason for liver transplants, and it will kill more people than Aids by 2020.

The scale of the problem has been recognised by the Government, which published an action plan to tackle it last year. But in a report published yesterday, the Hepatitis C Trust, a charity for sufferers, said that Britain was at the bottom of the European league on treatment, with fewer than 2 per cent of cases receiving drugs, compared with 15 per cent in France.

Drug treatment costs £6,000 to £12,000 per case, and cures more than half of sufferers. It has been approved for use on the NHS by the National Institute for Health and Clinical Excellence (Nice), but the disease has no symptoms in its early stages and only one in 10 sufferers knows they are infected.

Charles Gore, chief executive of the Hepatitis C Trust, which produced the report, Losing the Fight Against Hepatitis C, said: "We have a dreadfully poor track record at diagnosing the disease. More than 400,000 people in the UK with the virus are completely unaware that they have been infected. As a consequence, they are not in a position to make lifestyle decisions that could reduce liver damage, and may inadvertently be putting others at risk of infection."

The disease can be spread through sharing needles in drug use or tattooing, snorting cocaine through a shared straw or banknote (the drug irritates the mucosal lining of the nose, making it bleed), sharing razors or toothbrushes, rarely through sex, and in childbirth (one in 20 infected mothers passes it to her baby).

Up to 30 per cent of those infected will suffer severe symptoms caused by chronic inflammation of the liver, including cirrhosis, liver cancer, and death over two or three decades.

William Rosenberg, professor of hepatology at the University of Southampton, said: "My hepatitis C clinic is full of lawyers, doctors, accountants and shopkeepers - responsible, professional middle-class people - who in their teens in the 1960s dabbled occasionally in drugs, for example by taking speed at weekends.

"There has been a major failure in the UK to address a public health epidemic. In France they diagnose five times more cases and treat 10 times more than we do. It is the same in Germany, Italy and Spain. Awareness of the problem is woefully low in the UK. Probably over 150,000 people in the UK will die unless they are treated."

The disease carried a stigma because of its association with drug use, he said. "That prejudice is very common. It is perceived as a low-life disease. People who are leading upstanding lives in the community with hepatitis C don't want to speak out about it, in the same way as people with cancer felt stigmatised 20 to 30 years ago."

Drug treatment with interferon and ribavirin can clear the virus from 40 to 80 per cent of patients, the report says.

Neil Hudson, 35: 'I was lucky I was diagnosed by accident'

Neil Hudson, 35, had to fight for treatment after discovering he was infected with hepatitis C during a routine test in 1999.

He contracted the virus through a blood transfusion nine years earlier when he was 20, seriously ill with pneumonia and septicaemia.

In intensive care and fighting for his life, he received 164 units of blood, one of which was contaminated with the virus. "I had to wait four months to see a liver specialist. I felt very isolated. I changed my diet, stopped drinking alcohol and made sure I had enough rest. In March 2000, seven months after finding out I had a fatal illness, I had a liver biopsy [test] which confirmed that the damage to my liver warranted treatment."

He then had to wait for the National Institute for Clinical Excellence to approve drug treatment with interferon. He wrote letters to his health authority and MP but they refused to sanction treatment before the NICE decision in January 2001.

His first round of treatment failed to clear the virus from his blood and he had to wait another 15 months before being offered a second chance with a different form of the drug. The second round of treatment finished in June 2004 and tests showed he was free of the virus earlier this year.

He said: "I was lucky I was diagnosed by accident. I feel better now at 35 than I did at 25 because I had this disease eating away at my liver day by day. We have inferior treatment in this country. We should be ... preventing the spread of hepatitis C, but we are not."

Hepatitis C: the facts

* The virus causes inflammation of the liver

* It is transmitted through blood, and possibly through semen and saliva

* Between 200,000 and 500,000 people in England and Wales are infected

* Most of those infected remain healthy and symptom free for many years

* Drug treatment over six to 12 months can eliminate the virus

* Without treatment, a quarter will develop liver disease or cirrhosis over 20 to 30 years

* Liver failure because of hepatitis C is the main cause of liver transplantation