Hepatitis C is an inflammation of the liver caused by the Hepatitis C virus. It affects 170 million people worldwide.

Hepatitis C is almost always transmitted through direct contact with infected blood. People who are at risk are those who, like Anita Roddick, had a blood transfusion or blood products before routine screening for blood used in transfusions was introduced in the 1990s.

The other major group of people at risk are those who inject drugs and don’t use a sterile needle and sterilised syringe together with the rest of the injection paraphernalia. Children born to mothers positive for Hepatitis C may also have the disease.

Those who work in the medical profession and have suffered “needle stick injuries” – the unintentional pricking of the hands by needles – can also be at risk. The last group are those who indulge in high-risk sexual behaviour. But although the virus is present in saliva and semen, it is rarely spread through sexual contact, unless there has been some bleeding, however slight.

The obvious precautions to take are to use screened blood – this is now always the case in the Western world, and have careful hygiene – it is not a good idea to share a toothbrush or old-fashioned razors. Sexual partners should be chosen with care and normal protective measures should be used.

One of the problems of Hepatitis C – perhaps the most sinister – is that the initial infection often passes unnoticed and its progress is initially insidious. It is known as the “silent disease” because it often doesn’t cause any trouble until 15, 20, even 30 years until after the infection has been transmitted.

The most common symptoms when it does begin to cause problems, is that the patient is tired all the time. Any patient who gets unexplained fatigue should always have a Hepatitis screen as well as a full blood count.

As the disease progresses, patients may be jaundiced, suffer from loss of appetite, aches, pains, anxieties and depression, and because the liver is inflamed, tenderness in the upper right-hand side of the abdomen.

The first stage of the disease – the initial infection – last about six months and is often unnoticed. In 20 per cent of cases this is the last trouble people will ever have from the virus as the immune system deals with it perfectly.

The rest continue to develop chronic long-term Hepatitis C - even though they may have no symptoms, the liver is being damaged by the virus. Evidence of liver damage may not show for 15-30 years after first infection. 20 per cent of chronic cases develop, as Anita Roddick has, cirrhosis. This is a fibrosis and scarring of the liver which eventually results in liver failure.

People most likely to develop liver disease are those who catch it in older age, are male or have other auto-immune problems, including HIV. Alcohol increases the risk of liver damage in people with Hepatitis C and this may be one of the rare reasons they should refrain from any drinking.

If the infection is recognised in time, there is now some drug treatment available. People who have reached the cirrhotic stage may also be given treatment, but will respond less well and may eventually need a liver transplant.

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