A campaign launched on Thursday calls on "yesterday's rebels" to get tested for hepatitis C.

It comes amid fears that thousands of people could have the virus without knowing it.

Hepatitis C is caught through blood to blood contact. But it is thought many people may have put themselves at risk through intravenous drug use, sharing cocaine equipment, body piercings or tattooing, and through unprotected sex.

The virus attacks the liver and can lead to cirrhosis, liver failure or cancer.

Many unaware

Estimates of the number of people infected with it in England and Wales vary considerably from 200,000 to 400,000. However, only a small proportion are diagnosed.

People can have the virus for more than 20 years before serious health concerns make them aware they are infected.

The Responsible Rebels campaign is being backed by the British Liver Trust, the Hepatitis C Trust, doctors and people living with the condition.

Dr Graham Foster, a consultant hepatologist at St Mary's Hospital in Paddington, said patients were typically in their mid to late 40s with responsible jobs and families.

"These people are often well-educated and may have experimented with drugs in their younger days," he said.

Nigel Hughes, chief executive of the British Liver Trust, said nine out of 10 people are unaware they have hepatitis C.

"The tragedy is that they may not find out until they have cirrhosis, liver failure and or liver cancer."

Public awareness

Charles Gore, chief executive of the Hepatitis C Trust said: "The immediate priority is to make the public aware that there are hundreds of thousands of people in the UK who have hepatitis C and don't know it.

"Hepatitis C is a killer yet once it has been diagnosed there is much that can be done, with treatment and with management. It is better to know that than to die."

Peter Bell, 54, who works at the British Film Institute, said he was typical of his generation and tried many things in his youth, which led to a spell of drug addiction.

"About 13 years ago I decided it was time to make a radical change in my life and ever since I have been clean," he said.

"But hepatitis C is one of the legacies from that time.

"The disease has had an enormous impact on my life but I have just finished a course of treatment that I hope will have permanently cleared the virus from my system."

Anyone concerned about hepatitis C is advised to go to their GP or local clinic for a blood test.