The word hepatitis means inflammation of the liver. There are many causes of hepatitis, including viruses, drugs, alcohol and poisons. The three viruses that most commonly cause hepatitis are termed A, B and C.
Hepatitis A, often referred to as infectious hepatitis, is a common cause of liver disease in childhood and in travellers to areas where there is poor hygiene and sanitation. It often results from eating or drinking contaminated food or water. It causes inflammation of the liver from which most people recover with no long-term problems.
The hepatitis B virus is found in blood and body fluids. For this reason intravenous drug users and those with many sexual partners are at greatest risk for hepatitis B (and also for HIV). Although more than 90 per cent of adults infected with this virus recover completely, it can cause ongoing or lifelong infection leading to liver failure. It can be passed from mother to infant and 90 per cent of infants carry the virus throughout their lives.
The virus that causes hepatitis C was first described in 1989, but has gained public attention following the tainted blood scandal in Canada. It is the most frequent type of hepatitis after A and B and has become the leading cause of chronic liver disease in North America. Over 80 per cent of people exposed to hepatitis C will develop a chronic liver infection. Often there are either no symptoms or only mild symptoms with initial or chronic infection.
Late in the illness this may change because hepatitis C can lead to scarring of the liver (cirrhosis) and liver cancer (hepatocellular carcinoma). In many centres it has surpassed alcohol as the leading cause of liver failure requiring liver transplant.
The virus is spread when a person has contact with infected blood. From one-half to one per cent of Canadians may be infected. High-risk groups include intravenous drug users (sharing needles, spoons, diluting fluid) and hemophiliacs (multiple transfusions) where infection rates may be as high as 60 to 90 per cent. Intravenous drug use accounts for most of the cases.
The Canadian Red Cross, now Canadian Blood Services, began screening blood donors for hepatitis C in 1990. If you received blood before this date you may be infected. Today you are very unlikely to be infected through a blood transfusion, although the risk is not zero (especially if the donor recently developed the illness). Health care workers may contract it from needle stick injuries. High-risk sexual behaviour (multiple sexual partners) accounts for a smaller percentage of cases. Hepatitis C can also be acquired through tattoos, body piercing and snorting cocaine.
In Canada about 10 per cent of those infected have no obvious risk factors. Often a person is tested for hepatitis C after the doctor has found abnormal blood tests indicating a liver problem.
Testing for hepatitis C can be done by getting a simple blood test through your doctor. The test measures antibodies (substances that fight infections) to the virus which develop after
exposure. Your doctor will also measure your liver enzymes (ALT) to see if there is liver damage caused by the virus. Special tests that look directly for the genetic material of the virus can be done. This test, called a PCR (Polymerase Chain Reaction), confirms the presence of the virus and is often done if a person is being considered for treatment.
Most patients infected with hepatitis C have no symptoms. When they do have symptoms, fatigue is a common complaint. Jaundice is not evident unless liver failure develops in the late stages of the disease. Studies of those infected show great variability in the course of the disease.
A person who is infected but has normal liver tests may have a life expectancy similar to a non-infected person. Those with elevated liver enzymes may progress to chronic liver disease. About 20 per cent of infected people may develop cirrhosis (severe liver scarring) over 20 years of infection. Cirrhosis can lead to complications of fluid retention in the abdomen (ascites) or bleeding from varicose veins in the esophagus (esophageal varices). If such problems arise the patient may require a liver transplant. Cirrhosis caused by hepatitis C also may lead to the development of liver cancer.
Treatments for hepatitis C are available but unfortunately they are associated with high costs, side-effects and do not work in everybody.
Interferon therapy was the first effective treatment. This drug works by boosting the immune system making it more difficult for the virus to survive and damage the liver. It is given by injections underneath the skin three times per week. Patients with elevated levels of liver enzymes in the blood are considered for treatment that lasts for up to 12 months. Only 10 to 25 per cent of people will have a long-term response to treatment with interferon resulting in clearing the virus. The response is even lower in patients with cirrhosis.
Interferon is associated with many side effects, most frequently flu-like symptoms and fatigue. It can also affect the level of important blood cells and may cause irritability and depression.
Recently, interferon has been combined with a new drug called ribavirin. The mechanism of action of ribavirin is poorly understood. It is taken in pill form twice per day and is well tolerated although it may cause dose-related, reversible anemia. The combination of both drugs given for one year results in long-term freedom from hepatitis C virus in 30 to 40 per cent of people. Patients infected with certain less common strains of the virus can stop treatment after six months with even better results.
People infected with hepatitis C should consider their blood infectious. If they are intravenous drug users they should never share needles or paraphernalia. They should not donate blood or be organ donors. They should not share razors or toothbrushes.
The risk of transmission of hepatitis through unprotected sex is much less than for HIV or hepatitis B. People in a relationship with only one sexual partner have a small chance, about two per cent over 20 years of sexual activity, of passing the virus to their partner. People with multiple sexual partners are at higher risk. An infected pregnant woman has a one to five per cent risk of passing hepatitis C to her newborn infant, usually during birth.
Infected people do not need to worry about passing the infection to others with casual contact. Handshakes, hugging and kissing do not spread this disease. There is no need to use separate utensils or washrooms.
Unlike hepatitis B, there is no vaccine for hepatitis C to help protect those in high-risk groups. People infected with hepatitis C should limit their alcohol intake. Alcohol itself can cause cirrhosis, and the combination of hepatitis C and alcohol speeds the progress toward cirrhosis. No safe level of alcohol intake has clearly been set, but infected people should probably have no more than two drinks per week. No other dietary or lifestyle changes have been shown to have an impact on the progress of the disease.
Those infected with hepatitis C should be vaccinated against hepatitis A and hepatitis B, if they have not had prior exposure. People infected with hepatitis C who are exposed to hepatitis A have a higher chance of developing liver failure and death. The hepatitis A vaccine is given as two injections and can prevent such complications.
Hepatitis C is a viral infection that can cause chronic liver disease. It is spread by blood to blood contact with an infected person. Although most people infected will have no symptoms it can lead to serious long-term health problems. Treatments are currently available for some infected patients. Ongoing research is needed to improve and perfect treatment for this common and potentially serious disease.