Family doctor

Overview:

• Hepatitis B is a caused by a virus that causes inflammation of the liver
• More than a third of the world's population may have been infected, it is estimated that 350 million have become chronic (long term carriers)
• About a quarter of chronic carriers develop serious liver disease e.g. cirrhosis and liver cancer
• Sexual transmission is the most common means of spread in Europe and North America. Those aged 15 to 24 are at highest risk
• It may be spread non-sexually in early childhood - this is a more common method of transmission in developing countries
• Most people make a full recovery
• About 10 percent of infected people will become carriers
• Symptoms include a flu-like illness and jaundice.
• Hepatitis B vaccination is safe, effective and offers the best chance of reducing infection. Immunisation is now routinely done in childhood in many countries.
• Those at high risk include homosexual men, children, and intravenous drug users

What is hepatitis B?

Hepatitis B is a viral infection that causes inflammation of the liver and is spread through contact with infected blood and other bodily fluids.

 In many parts of the world it is spread non-sexually in early childhood (playground type contact)In fact most of the worlds chronic carriers will have acquired it this way in early childhood.

It is a common virus and much more infectious than HIV. Kissing and sexual contact can spread the disease.

The most common way for adults to get it is through intravenous drug use and sexual intercourse with a carrier. It is not spread by casual contact like holding hands.

Procedures like body piercing and tattooing can also spread the disease.

Complications include cirrhosis of the liver, liver failure and liver cancer, and these cause one to two million deaths a year around the world.

During the first half of 1990, the rate of the most common form of liver cancer increased by more than 70 percent in the United States, with hepatitis B and C the most likely cause.

Five to ten percent of those infected with hepatitis B will become carriers. They are then able to pass the virus to other people. Carriers are "antigen positive" - this means they still have a part of the virus in their blood. Carriers who are e-Antigen positive are particularly highly infectious.

It can take many months to know if a patient is becoming a carrier and careful follow up and tests are needed.

People who make a full recovery and do not become carriers have antibodies (antibody positive), but no virus antigen (antigen negative) on blood testing .They cannot pass the virus on to others.If you have had hepatitis B, it is important to check with your doctor as to whether you are a carrier and can pass the virus on.

Infection occurs during contact with the early stage of infection or from an established carrier.

Anyone can get hepatitis B but those at high risk include drug users who share needles, health care workers, homosexual men with several partners, prostitutes, children in day care, dialysis patients, and babies born to mothers with hepatitis B, and people living very closely with an infectious carrier.

What are the symptoms?

There are two forms of hepatitis B, acute and chronic. Symptoms of acute hepatitis B are a flu-like illness and jaundice (yellow skin and eyes). The chronic form may take months to develop and is more serious. In a proportion of chronic hepatitis sufferers, complications like cirrhosis of the liver, liver failure and cancer may develop, usually after many years.

Diagnosis is based on blood tests which may show the presence of the virus, or antibodies to the virus. During the early acute phase, the liver function tests are very raised and normalize with time. The liver tests may remain mildly abnormal in chronic carriers. Damage to the liver may continue in chronic cases, even if the liver tests remain normal.

 A liver biopsy may be needed in chronic cases to determine what is happening to the liver.

Occasionally sufferers will experience joint pain, hives or a rash.

The liver becomes abnormal one to 10 days after infection with the virus, and symptoms appear in about two to six months after exposure, and usually within three months.

Some people do not show any symptoms.

There is an 80 percent chance of an infected mother passing the virus to her baby. Infected infants have about an 80 percent chance of developing chronic hepatitis and becoming a carrier.

What can be done to help?

There is no cure for hepatitis B once the symptoms appear. Bed rest and good general nursing care is the best remedy.

Patients are advised to eat well and to avoid alcohol (usually for several months - until the liver fully recovers).

Exposure to the virus can be treated within 24 hours to one week of contact. Treatment involves injections of immune globulin which provides some antibodies to fight the virus. The first dose of the vaccine can be given at the same time .

Most people who contract the disease make a full recovery, although some will need to be hospitalised. There is a small but real risk of death in severe cases.

Chronic (i.e. long term) hepatitis B sufferers who experience liver failure may need a liver transplant.

Drug treatment of chronic hepatitis B

Several drugs are available to help treat those who have chronic hepatitis, particularly those who have high levels of viral replication as indicated by being "e-Antigen positive", and with signs of liver inflammation.

Treatment is arranged by specialists and a liver biopsy is usually undertaken prior to treatment.

Drugs include

1-Interferon Alfa

Until recently this was the only available drug available. It can help reduce the rate of viral replication in up to 20 % of patients. Side effects(flu-like feeling) are a problem for some patients.

2-Lamivudine

This is similarly effective to interferon,but has much fewer side effects. Long term, the development of resistance is a significant problem.

Combinations of the above drugs may be used .

Stronger and possibly more effective drugs are under research (e.g. - adefovir).

The above drugs are expensive and this may limit their availability .

How can it be prevented?

Safe and effective vaccination is available to prevent hepatitis B, and immunisation is recommended by the World Health Organization for all children. Immunisation of adolescents not immunised in childhood should be considered. Homosexual men, injecting drug users, health care workers, people with liver failure, and prison inmates may also benefit from the vaccine.

 A special hepatitis B immune globulin is also available for people who are exposed to the virus. The first dose of vaccination can be given at the same time.

The use of condoms may help prevent the spread of the virus. The virus may be in saliva and spread by kissing .

Carriers who cannot get rid of the virus ("antigen positive") have a responsibility to tell sexual partners, dentists, and doctors about their condition. They should follow basic hygiene practices to ensure others are not put at risk. They should not share razors, toothbrushes or any object that could be exposed to blood. Immunisation of sexual partner(s) should be arranged and will protect them from hepatitis B.

Household members with a carrier in the home should be immunised with the hepatitis B vaccine.

Future trends

The best strategy will be immunisation to prevent the massive worldwide impact of this serious disease.

It is hoped that more effective anti-viral drugs combinations will be developed to help treat people with the chronic form. Resistance and cost are likely to remain problematic.

Scientists are studying the body's immune response to hepatitis viruses and investigating how they lead to recovery or chronic disease.

Researchers are also looking ways to make anti-viral drugs less toxic, and how to boost the immune response in babies to stop them catching the virus off their mothers.

Getting help

You doctor will be able to advice you on testing, diagnosis and vaccination. People with chronic infection should be under the review of a gastroenterologist or liver specialist.