Hepatitis B

Description

• Hepatitis B is a common infection in South African children.
• A significant number of South African adults are hepatitis B carriers.
• Chronic hepatitis B can cause irreversible liver damage.
• There are safe, effective vaccines against hepatitis B.

“Hepatitis” simply means that the liver is inflamed. Signs that indicate that the liver is inflamed include:

• pain in the right upper abdomen
• fever
• nausea and vomiting
• a yellow tinge to the eyes and skin (jaundice).

There are a variety of causes of liver inflammation. A common cause is excessive alcohol intake, since alcohol is a liver toxin. Many medications are toxic for the liver, for example some of the drugs used to treat tuberculosis (TB). Herbal medicines can also be liver toxins. There are a number of infectious causes of hepatitis, of which the most important are the hepatitis viruses.

Cause

Hepatitis B is caused by the Hepatitis B virus which is a blood-borne virus. Hepatitis B is highly infectious. It is estimated to be about 50 times more infectious than HIV. It is mostly spread by very close contact with an infected person, which allows exchange of minute quantities of blood through tiny grazes or cuts. This sort of spread can occur through:

• sex
• rough play amongst children
• sharing toothbrushes or razors
• direct contact with e.g. a bleeding wound.

More specific high-risk circumstances where the spread of hepatitis B can occur:

• tattooing or tribal scarification with unsterile implements
• between intra-venous drug abusers who share needles and syringes
• between patients and staff in hospital settings e.g. haemodialysis units
• potentially by blood transfusion. Since all blood donations are screened for Hepatitis B and C prior to use, the risk of acquiring viral hepatitis from a blood transfusion is low – in the region of 1 in 10 000 or less.

Hepatitis B can be passed from an infected mother to her baby. (See “complications”).

Note that despite the fact that hepatitis B is found in the blood, there is no convincing evidence that they are spread by mosquitoes or other biting insects.

Occasionally, viruses that are not true hepatitis viruses can cause significant liver inflammation. It is not uncommon to have a mild hepatitis during glandular fever (Epstein-Barr virus) or during the similar illness cause by initial infection with Cytomegalovirus. Very, very rarely, and fairly unpredictably, Herpes Simplex virus can cause an aggressive form of hepatitis that is usually rapidly fatal.

When the hepatitis B virus reaches the liver, it infects the liver cells and multiplies inside them. The body's immune system can recognise virus-infected cells and will attempt to destroy these cells. This immune attack by white blood cells causes liver cell damage and inflammation.

Certain enzymes that are usually active inside the liver cells are released from damaged cells into the blood and can be detected by blood tests, thus confirming that there is a hepatitis.

The liver is also the site of production of certain blood proteins such as albumin and clotting factors, and levels of these proteins may be low in severe or long-standing hepatitis.

Liver inflammation will also involve swelling of the liver. Swelling causes blockage of the bile ducts in the liver so that the bile that should flow into the gall bladder is trapped in the liver. Since it cannot escape, the yellow-green bile starts to be absorbed into the blood stream from the liver, and will circulate to the skin and eyes, causing the yellow discoloration known as “jaundice”. Swelling of the liver is also what causes pain in the abdomen during hepatitis. (The liver is located in the right upper quarter of the abdomen). A health care professional will often be able to detect that the liver is enlarged and tender during examination of the abdomen.

Prevalence

Hepatitis B is widespread in sub-Saharan Africa and South Africa. In South Africa, up till now, hepatitis B has been particularly common in two age groups: young children and young sexually active adults. Past studies have found that about 8% of children under one and almost 16% of children under 6 years of age are infected with hepatitis B. Between 10-18% of South African adults are hepatitis B virus carriers. Infection has been more common in some areas of the country, for example the Eastern Cape Province and Kwazulu-Natal. South Africa has had one of the highest rates of liver cancer in the world, and this is linked to the high rate of Hepatitis B. Since vaccination of all children against Hepatitis B was started in 1995, it is hoped that the disease and its complications will soon become far less prevalent.

When to see a doctor

The symptoms of hepatitis B already described in Symptoms would require a visit to the doctor. The following are potentially serious symptoms which definitely require immediate attention.

• persistent vomiting for longer than six hours
• extreme drowsiness, confusion or restlessness
• unusual bruising or bleeding
• jaundice continuing for longer than three weeks

Diagnosis

The symptoms of hepatitis and the fact that viral hepatitis is so common in South Africa will usually lead a health care professional to suspect the disease early on. Blood tests can be done to confirm that there is hepatitis, and its severity, and these tests can even give some clues as to whether the cause is viral.

However, one cannot tell one type of viral hepatitis from another without specific tests for the different viruses. Laboratory diagnosis of hepatitis B requires very straightforward blood tests. Some additional tests are available that can give information about whether this is a recent or chronic infection, and about how active the virus is.

The following tests are used to diagnose hepatitis B.

TEST NAME – INTERPRETATION

• Hepatitis B surface (s) antigen – if positive, the person has hepatitis B infection
• Hepatitis B early (e) antigen- indicates very active infection; the person is highly infectious. If this antigen persists for more than six months, that individual is now classified as a chronic carrier of this infection and is infectious.
• Hepatitis B early (e) antibody – usually indicates less active infection
• Hepatitis B core IgM antibody – usually indicates recent, rather than chronic infection
• Hepatitis B core IgG antibody – found in anyone who is or has been infected with hepatitis B
• Hepatitis B surface (s) antibody – indicates immunity to hepatitis B

Treatment

Home

• If the person with hepatitis feels unwell enough to be in bed, they should rest in bed. Otherwise, if there is no fever, normal activities can be continued.
• A temperature of greater than 39 degrees Celsius can be treated with paracetamol. However, this must be done with caution and in consultation with a physician because paracetamol is processed in the liver and a person with viral hepatitis may not deal with this drug as effectively as a person without hepatitis.
• A person with hepatitis will probably be inclined to avoid fatty foods. Otherwise a regular diet can be followed. If their appetite is poor, then fruit juice and other liquids should be encouraged.
• Avoid alcohol.

Medical treatments

An acute hepatitis (a new infection) is not given any specific treatment, because there is no effective treatment available. Recovery is dependent on the person's own immune response to the virus infection. Any of the different complications might require medical treatment in hospital. Even if a person appears to make a full recovery, follow-up blood tests should be done to show whether the infection has been cleared or whether it has persisted as a chronic infection.

There are limited possibilities for the treatment of chronic hepatitis B. Chronic active hepatitis B is probably best managed by specialists who have experience with the few drug treatments available. Drugs such as alpha-interferon and lamivudine are sometimes successful for managing or eradicating chronic hepatitis B. A liver transplant may be required to save a person with end-stage liver damage.

Sound general advice for those with chronic hepatitis B can be found at http://www.immunize.org/catg.d/p4120.htm

Prevention

A small percentage of people will die during severe early hepatitis B and many more from the long-term consequences of chronic infection. As treatment possibilities are limited, avoiding hepatitis B is most important.

As hepatitis B takes several months to clear from the blood, a person will probably be well enough to return to their normal activities before they become non-infectious. In this case, they should avoid any sort of contact with others that might pose an infection risk (see “cause”). Normal school activities (except for contact sports) or office activities do not pose a risk to others. Follow-up blood tests will show when a person has cleared the virus and is no longer infectious.

Advice on preventing the spread of blood-borne diseases, especially where children are involved, can be found at http://www.pkids.org/universal precautions.htm

Immunoglobulin for preventing hepatitis B

“Immunoglobulins” may be more familiarly known as antibodies. Immunoglobulin preparations are produced from donated blood. A proportion of blood donors will be immune to one or more of the hepatitis viruses, and their blood can be used to “harvest” anti-hepatitis immunoglobulin. The immunoglobulin, given by injection to another person, can provide them with “instant immunity” against the virus. This is used to protect people who have been exposed to hepatitis B and have not been vaccinated in the past. However, the immunoglobulin will not be effective if given too late after exposure when the virus has already established an infection. If you or your child have had known exposure to hepatitis B, your doctor would have to assess and discuss with you whether to use immunoglobulin. Hepatitis B immunoglobulin can be used following any accidental exposure to hepatitis B, and is used to protect new-born babies when the mother is infected (see below). Immunoglobulin and a first dose of the hepatitis B vaccine can be given simultaneously.

Vaccination

In South Africa, vaccination against hepatitis B has been part of the routine childhood immunisation programme since 1995. The vaccine is given to children at the ages of 6, 10 and 14 weeks, along with the oral polio vaccine and “DPT” vaccine. (The other vaccines do not interfere with the hepatitis B vaccine, and there is no increased risk of side-effects when they are given at the same time.)

Up until 1995, hepatitis B vaccine was only given to people in high risk groups, particularly health care workers. Children and adults born before 1995 will probably not have been vaccinated against hepatitis B. It is advisable for young people who are homosexually or heterosexually active to be vaccinated against hepatitis B. When a person is a known hepatitis B carrier, it is important for all family/household members to be vaccinated against hepatitis B. In older children and adults, the vaccine is given in three doses, usually over six months. It is important that three doses of vaccine be given, with at least one month spacing between them, in order for good immunity to be achieved.

Preventing mother to baby transmission

The chance of hepatitis B transmission from a mother to her baby can be much reduced if immunoglobulin and vaccine are given to the baby at birth. The baby will then need two subsequent doses of vaccine and should be monitored to see if he or she has been successfully protected.

(Reviewed by Dr Eftyhia Vardas, University of the Witwatersrand)

The information provided in this article was correct at the time of publishing. At Mediclinic we endeavour to provide our patients and readers with accurate and reliable information, which is why we continually review and update our content. However, due to the dynamic nature of clinical information and medicine, some information may from time to time become outdated prior to revision.