Lawyers, who this week go to court, say Britain failed to introduce a test for hepatitis C when one was available and being used in other countries. It is claimed that some kind of testing was available for nearly four years before a test was introduced in the UK in 1991.
So far, 160 people have signed up to the lawsuit, but the number of people taking action is expected to reach 400 by the time lead cases are selected for trial later this year, said solicitor Anthony Mallen, who is coordinating the action and who will attend the British Liver Trust conference on Tuesday.
It is estimated that one in four of those infected will develop serious liver damage, including cancer and cirrhosis. Many are also expected to need liver transplants, too.
The case, the first of its kind under the Consumer Protection Act, centres on people who say they were infected with hepatitis C through blood transfusions between 1988 and 1991, when the test was brought in.
Hepatitis C, or HCV, is a blood-borne infection causing inflammation of the liver and is the most common cause of chronic liver disease. One problem with the disease is that 90 per cent of patients show no symptoms when first infected. Random sampling of blood tests indicate that the disease is now so prevalent that about 500,000 people in this country may be infected.
"The essence of the claim is that this country should have brought in testing earlier," said Mr Mallen. "We say that the Consumer Protection Act creates strict liability or absolute liability. We say that blood products are products within the meaning of the Act and that those products were defective because of the contamination with hepatitis C.
"If that is established it is incumbent upon the defendants of the National Blood Authority to prove that there were at the time no scientific methods available to exclude this infection of blood. In other words, once we have proved it is a product, the burden of proof transfers to them."
A spokesman for the NBA referred comment to the Department of Health, which declined to comment on the case.
The British Liver Trust has a helpline on 01437 276328.Reuse content