Hepatitis B is a Devastating Global Healthcare Issue
75% of long-term carriers live in Asia Pacific5
•350 million long-term carriers worldwide1
•Up to 25% will die due to hepatitis B or related complications2
•Around 1 million die each year from HBV infection3, making it the 9th leading cause of death worldwide4
1 WHO 1998; 2 Mast 1993; 3 Lee 1997; 4Boag 1991; 5 Gust 1996
Hepatitis – Disease Terminology
Acute hepatitis
Short-term hepatitis, during which the body’s immune system clears the virus from the body within 6 months
Chronic hepatitis
Long-term hepatitis, in which the infection persists beyond 6 months because the body’s immune system cannot clear the virus from the body
How Hepatitis B is Acquired?
•In the Asia Pacific region, most people acquire the virus at or near the time of birth1 - 9 out of 10 of those infected with hepatitis B will still be infected when they reach adulthood2
•In the rest of the world, hepatitis B virus is more likely acquired in adolescence or adult life through sexual contact or exposure to contaminated blood1
1 Margolis et al. 1991; 2 Thomas 1996
How the Infection is Acquired in the West?
Transfusion and |
Newborns of long-term |
transplant recipients |
carriers |
Individuals with |
Intravenous |
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multiple |
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drug users |
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sexual partners |
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Healthcare |
Prisoners and other |
workers |
institutionalised people |
Hepatitis B – Diagnosis Terminology
HBeAg |
Viral protein produced when virus |
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replicates |
|
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HBV DNAGenetic material of the hepatitis B virus |
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ALT/AST |
Liver enzymes (proteins)-detected at high |
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levels in blood when liver cells are |
damaged |
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HistologyLiver tissue sample seen under the microscope to assess liver damage
Diagnosis of Chronic Hepatitis B
•Medical history and physical examination
•Tests needed because majority of patients have no symptoms
•Blood Tests
–Viral replication (HBV DNA and HBeAg levels)
–Liver damage (liver enzymes - ALT/AST)
•Liver tissue sample (histology) - allows determination of the extent of liver damage
Signs and Symptoms of HBV Infection
The majority of patients with chronic hepatitis B have no symptoms
Short-Term Infection
•Tiredness or “flu-like” symptoms
•Nausea or stomach ache
•Diarrhoea
•Skin rash
•Yellow eyes/skin (jaundice)
•Light-coloured stools
•Dark yellow urine
Long-Term Infection
•Same symptoms as acute
•Muscles and joints ache
•Weakness
•Signs and symptoms of cirrhosis
Universal Hepatitis B Vaccination
The Strategy
•All infants to be immunised before the age of 18 months – regardless of country
•In 1998, 80 countries have achieved this goal
The Experience
•Other childhood vaccines do not interfere with response
•Protection lasts >10 years and booster doses not required
•Screening of pregnant women for HBV markers, ensuring immediate vaccination of infants borne to HBsAg+ve mothers
Global Control of Hepatitis B
•The two most important interventions in the global control of hepatitis B are……….
–the integration of hepatitis B vaccine into national immunisation schedules and
–effective treatment of the many millions of chronic carriers of hepatitis B
Types of viral Hepatitis
Hepatitis How is it acquired?
A Oral via contaminated food or water B Blood/body fluids and mother-to-child C Blood/body fluids and mother-to-child
D Blood/body fluids (only found with hepatitis B virus)
E Oral via contaminated water G Blood
Hoofnagle 1994; Linnen et al. 1996