Hepatitis B Virus (HBV): Transmission, Symptoms, and Vaccination

Overview of Hepatitis B Virus (HBV)

Hepatitis B virus (HBV) infects the liver, causing inflammation and potentially leading to cirrhosis or liver cancer. Symptoms may vary or be absent altogether.

Common symptoms include yellow skin (jaundice), yellowing eyes, fatigue, loss of appetite, and nausea.

Global Impact and Prevalence

The World Health Organisation estimates that over 350 million people worldwide are chronically infected with HBV. High-prevalence regions include sub-Saharan Africa, most of Asia, and the Pacific islands.

In the UK, HBV prevalence is low but varies across the country. The annual number of new infections has decreased from around 260,000 in the 1980s to approximately 60,000 in 2004, with higher rates among those aged 20-49.

Transmission and Risk Factors

Hepatitis B is primarily transmitted through:

• Sexual contact with an infected person
• Sharing needles or syringes for drug injection
• From mother to baby during childbirth
• Exposure to contaminated sharp objects at work

It is not transmitted through casual contact such as handshakes, sharing food, or using public facilities like swimming pools.

Immunity and Vaccination

Most adults (90%) clear the virus within a few months and develop immunity. About 10% develop chronic infection, where the virus remains in the blood and damages liver cells over time.

A vaccine for hepatitis B is available, administered in 3 doses over 6 months. It is safe and effective, with no need for booster doses as immune memory remains indefinitely post-immunisation.

Occupational Considerations

Employees in certain professions exposed to bloodborne pathogens should be offered the HBV vaccine free of charge. These professions include:

• First aid administrators
• Medical and dental staff
• Custodial staff handling medical waste