How is Hepatitis B spread?
Hepatitis B is spread by contact with blood and other bodily fluids
– usually through an opening in the skin or contact with internal
lining surfaces of the body.
The ways in which people can be infected with the virus include:
1. Mother to child where the mother is a carrier of hepatitis B. This
usually happens around the time of birth. This is the most common way
for the virus to spread in some parts of the world eg. Asia.
2. By the use of injecting drugs (at any time in the past or present).
3. By unprotected sexual contact
4. By blood transfusion. This is extremely rare these days in Australia
since rigorous testing was introduced.
5. By tattooing with unsterilised needles
6. By close family contact
7. By accidental needle stick injury or by splashing with infected
blood or body fluids – usually within the healthcare setting.
What damage can Hepatitis B cause?
The outcome of hepatitis B infection depends largely on the age at
which someone is infected. Babies who are infected at birth almost always
go on to become long-term (chronic) carriers of the virus.
However the infection at birth is silent and the babies appear healthy
and do not usually become jaundiced (yellow). Although these people
often appear perfectly healthy for many years, they can become unwell
after 20 years or more. Cirrhosis (severe scarring) and liver cancer
can occur in chronic carriers who acquired hepatitis B early in life.
If
a teenager or adult becomes infected with the virus there is about a
50% chance that they will become ill and develop jaundice (turn yellow).
This illness is called acute hepatitis. However, in the other 50% of
cases, there is no jaundice. Adults have a good chance of being able
to clear the virus from the body naturally and these individuals are
then immune to the disease and do not go on to develop long-term liver
damage.
In approximately 5-10% of cases, adults are unable to get rid of the
virus, and become long-term (chronic) carriers. Generally such people
remain in good health for many years. However there is a chance that
such people will develop cirrhosis and liver cancer over many years
or decades.
How can the doctor tell if you have Hepatitis
B and if there is damage to the liver?
There are many tests that can assist doctors in assessing liver damage
or the likelihood of future liver damage from hepatitis B. The interpretation
of these tests is not always straightforward and may require specialist
advice. Some of these tests include:
• Specific hepatitis B blood tests to determine whether or not
you are infected with the virus; whether the virus is continuing to
multiply in the liver; whether you are currently infectious for the
virus or whether you have had the virus, cleared it and now have immunity
to hepatitis B.
• Liver function tests: blood tests which give an estimate of
liver inflammation or damage. The ALT (alanine amino transferase) test
is a reasonably good guide. Other parts of the liver function tests
can help the doctor assess whether or not there may be cirrhosis present.
• Liver ultrasound scan: these tests use inaudible sound
waves to take pictures of the liver to assist in diagnosing cirrhosis,
fatty liver or liver cancer.
• Liver biopsy: This is the removal of a tiny piece of liver
under local anaesthetic for examination to determine how much scarring
there is in the liver. The liver biopsy is the most accurate way of
assessing this.
• Alpha-fetoprotein: a blood test which can sometimes detect
liver cancer.
Is there any treatment for Hepatitis B?
Those people who have immunity and normal liver function tests do not
need any treatment. People who are chronic hepatitis B carriers without
liver damage do not require treatment but should see their doctor annually
for a check up.
However, if there is liver damage the doctor may consider using an
anti-viral medicine. The antiviral treatments are effective in about
30% of people who meet specific criteria. There are currently two main
types of anti-viral medications – Interferon and Lamivudine.
Usually the assessment and decision to treat hepatitis B is carried
out by a liver specialist.
People who already have cirrhosis of the liver will generally be kept
under close supervision by their doctor. Sometimes regular ultrasound
examinations and alpha-fetoprotein levels are recommended. People with
very advanced disease may be referred to a liver transplant unit for
assessment for a liver transplant.
What else can be done to improve the liver
if you have Hepatitis B?
Carriers of hepatitis B should eat a normal healthy diet. Alcohol should
be minimised or avoided. Care should be taken to avoid contracting other
blood-borne viruses (eg. the practice of safe sex and not sharing injecting
equipment).
What about Vaccination?
The hepatitis B vaccine is very safe and relatively inexpensive. It
is also very effective and gives good immunity in about 95% of the population.
The vaccine is usually given in three injections over six months.
Certain groups of people in the community are eligible for free hepatitis
B vaccination. For more information on this, check with your doctor.
If you are already a carrier of hepatitis B it is a good idea to be
vaccinated against hepatitis A as this virus could cause further liver
damage.
Who should be vaccinated?
Vaccination can be requested from a general practitioner or local
council. It is recommended that the following broad categories of people
be vaccinated.
1. All babies and adolescents who have not had hepatitis B vaccination
previously.
2. Babies of infected mothers (all pregnant women should be tested
for hepatitis B)
3. People who have had accidental exposure (eg. at work)
4. Health care workers
5. Household, family or sexual contacts of carriers of hepatitis B
6. Sexually active homosexual or bisexual men
7. Sex industry workers
8. Injecting drug users
9. Renal dialysis patients
10. Clients and staff of institutions for the intellectually disabled
and those in close contact with the de-institutionalised.
11. Aboriginal and Torres Strait Islanders
12. Haemophiliacs and others who may need multiple blood or blood product
transfusions, especially if they are given overseas.
13. Prisoners and prison staff
14. International travellers
15. People playing contact sport
16. Child care workers
17. People with other liver diseases
18. Embalmers
19. People working in accident and emergency services
ACKNOWLEDGEMENTS
The Digestive Health Foundation, which is the educational arm of the
Gastroenterological Society of Australia. Members of the foundation
are drawn from physicians, surgeons, scientists and other medical specialties
with an interest in GI disorders.
www.health.qld.gov.au
- access for a brochure on Hepatitis B
