Hepatitis B is a viral infection. It is spread from contact with the blood or other bodily fluids from an infected person. Hepatitis B can be found in blood, saliva, semen and vaginal fluid. It is therefore mainly transmitted through unprotected sexual intercourse or by drug users sharing needles and other contaminated injecting equipment. It can also be spread by infected mothers to their babies during child birth.

Most people infected with the Hepatitis B virus are unaware of the infection as they may have no symptoms or symptoms may only become apparent several months after exposure to the virus.

Hepatitis B (HBV) forms part of a group of viruses (which include hepatitis A, C, D, E and G) that mainly attack the liver. Hepatitis means “inflammation of the liver”. Other causes of hepatitis include excessive alcohol intake and certain drugs including medicines taken in overdose. The liver is a large organ located in the upper abdomen, mainly on the right side. It has many hundreds of functions which are essential for our survival and well being. Some of its major roles are summarised below;

  • Storing fuel for the body in the form of glycogen which is made from sugars such as glucose. When glucose is required by body cells, the liver breaks down glycogen, releasing glucose into the bloodstream.
  • Processing fats and proteins obtained from food.
  • The production of clotting factors. These are proteins which enable blood to clot.
  • The safe processing and removal of alcohol.
  • The safe processing of many poisons and toxins from the body.
  • The processing of many medicines.
  • The production of bile which is used to aid fat digestion in the gut.
  • The production of plasma proteins (mainly albumin) which are essential for fluid regulation within blood and the circulatory system.
  • The storage of elements and vitamins such as Vitamins A, D, E, K and iron.
  • The production of some antibodies to aid natural immunity.

HBV is a highly contagious viral infection. It is thought to be 100 times more infectious than HIV. Most individuals exposed to HBV develop an acute infection which is usually short lived. A minority of infected adults and the majority of infected babies develop chronic Hepatitis B. Most chronic HBV sufferers will remain well. However, these individuals can transmit the virus through sexual contact or by other means and are called “carriers”. Some infected individuals suffer from intermittent symptoms but others can go on to develop serious liver damage.

In the UK and most other developed countries the incidence of HBV is low. However, worldwide and especially in some parts of Africa and South East Asia it is much more prevalent. It is thought that in some areas 10% of the population may have chronic HBV infection.

How is Hepatitis B contracted?

Hepatitis B infection is contracted by someone who is not immune to this virus and who then comes into contact with someone with infected blood or other infected bodily fluids. Most infected people worldwide are unaware of their infection. Methods of spread can be divided into 2 main categories:

1. Vertical Transmission (from mother to baby): this is the most common reason for contracting HBV infection worldwide and occurs during birth of the baby from an infected mother. It may also occur during breast feeding. The infected mother may be unaware of her or her newborn’s infection. However, vertical transmission is very rare in most developed countries.

2. Horizontal Transmission (from person to person): this can happen in several different ways and can involve contact with infected blood, semen, vaginal fluid or saliva and is the most frequent method of spread in most developed countries. Examples of this include:

  • Unprotected sexual contact with an infected partner;
  • Contact with infected blood through an open wound, cut or other area of broken skin;
  • The sharing of blood contaminated needles, syringes and other equipment by drug users;
  • Needle stick injuries to healthcare workers and laboratory technicians with equipment contaminated with infected fluids;
  • Poorly sterilised tattooing and body piercing equipment;
  • Blood transfusions in countries where there is no routine testing of donor blood for blood borne infections;
  • There is a very small risk of contracting HBV from the sharing of toothbrushes, razors and towels.

HBV can not be spread with everyday activities such as holding hands, hugging, coughing, sneezing or the sharing of crockery.

What are the symptoms of Hepatitis B infection?

Hepatitis B infection can be divided into acute and chronic phases.

1. Acute Phase

The incubation period for HBV is between 1 to 6 months. Most people will develop no symptoms on contracting this virus although they themselves may go on to pass this virus to others. However, some will develop symptoms during the acute phase within the incubation period. These symptoms include:

  • General flu like symptoms with lethargy, nausea, vomiting, diarrhea, loss of appetite, headaches, fever, general aches and pains;
  • Abdominal pains;
  • Jaundice (when an individual looks yellow). Jaundice develops with a build up of bilirubin which causes the whites of eyes and skin to appear yellow. It may also turn urine very dark and faeces very pale. Jaundice can also cause itching of the skin.
  • Very rarely acute Hepatitis B leads to a severe infection called Fulminant Hepatitis B. Symptoms of this include collapsing, severe jaundice and abdominal distention. This can be a life threatening condition and must be treated quickly.

Symptoms of acute HBV may persist for a few weeks until the immune system can eradicate the virus or bring it under control. Following the acute phase 90% of adults clear the infection within 3 to 6 months. These individuals are therefore no longer infectious and are immune to further HBV contact. However, in 10% of adults the infection becomes chronic (long term). This may happen whether or not any symptoms develop in the acute phase. However, the situation in babies is reversed, with 90% of babies and young children infected by their mothers having chronic HBV.

2. chronic phase

Chronic infection occurs in individuals where the virus remains for longer than 6 months. Of these chronic sufferers approximately two-thirds of individuals will remain well. These “carriers” are sometimes said to have “chronic inactive Hepatitis B”. These individuals may be aware or unaware of their HBV status but will still pass on the HBV infection to others who may go onto develop serious symptoms. Other individuals go on to develop a degree of persistent Hepatitis (inflammation of the liver) and this is called “chronic active Hepatitis B”. Symptoms of this are very similar to those described in the acute phase. These individuals can have an intolerance of alcohol, abdominal pains and depression. However, some individuals may have Hepatitis without symptoms and the symptoms can vary in frequency and severity.

Unfortunately a small number of chronic HBV sufferers go on to develop liver cirrhosis (irreversible scarring of the liver). This potentially serious condition can lead to liver failure and eventually liver cancer. However, this process may take many years. Occasionally other organs such as the kidneys may be damaged in a small minority of chronic HBV sufferers.

How is Hepatitis B diagnosed?

Hepatitis B infection can be detected with a blood test. This test detects Hepatitis B surface antigen (HbsAg). This is a protein on the surface of the virus. If the HbsAg test is positive then the infection is present and further tests will be required. These tests detect other parts of the virus and can detect the activity and severity of the infection. Other blood tests called liver function tests (LFT) indicate the extent of liver damage. An ultrasound scan may also be required but ultimately the true extent of liver involvement and damage can only be assessed with a liver biopsy.

How do you treat Hepatitis B infection?

Treatment options for HBV depend on whether an individual is in the acute or chronic phase of the infection. There is no specific treatment in the acute phase of HBV. However, if an individual has symptoms such as for example pain then treatment aims to reduce these symptoms. Therefore, advice may be given by doctors regarding pain killers, adequate rest, adequate fluid intake, a healthy diet and alcohol avoidance. Most people in the acute phase tend to be free from symptoms and therefore require no treatment. If symptoms do develop they usually last around 2 months before resolving. In severe Hepatitis, assessment and specialist treatment will be required by a dedicated liver unit. However, these measures can not prevent an acute infection becoming chronic.

Treatment of chronic HBV sufferers is required if active disease is present. This will again involve assessment and advice from a dedicated specialist liver unit to prevent progression of the active disease to severe Hepatitis and cirrhosis. Treatment with anti-viral medication stops the virus from multiplying thus preventing or reducing the severity of liver damage. Examples of anti-viral medication include interferon and lemivudine. These anti-viral treatments do not work in all patients and many sufferers are affected by side-effects from the medication. Those individuals with severe liver damage such as cirrhosis may require a liver transplant. Unfortunately, this new liver will also be infected with the Hepatitis B virus and thus may also be at risk of liver damage after several years.

Scroll to Top