Hepatitis B Health Article

Definition

Hepatitis B is a liver disease caused by the hepatitis B virus (HBV).

Description

Hepatitis B is a form of viral hepatitis that is also known as serum hepatitis, due to its ability to be spread through body fluids and blood. HBV can cause lifelong infection, cirrhosis (scarring) of the liver, liver cancer, liver failure, and death. Hepatitis B is a more severe liver disease than hepatitis A, and asymptomatic infections occur frequently. Chronic hepatitis B infection may take one of two forms: chronic persistent hepatitis, a condition characterized by persistence of the virus but in which liver damage is minimal; and chronic active hepatitis, in which there is aggressive destruction of liver tissue and rapid progression to cirrhosis or liver failure.

Transmission

Transmission of HBV occurs through blood and body fluid exposure such as blood, semen, vaginal secretions, or saliva. Hepatitis B is not spread through food or water or by casual contact. Infants may also develop the disease if they are born to a mother who has the virus. Infected children often spread the virus to other children if there is frequent contact or a child has many scrapes or cuts. The common modes of transmission of hepatitis B are as follows:

• children born to mothers who have hepatitis B (the illness may present up to five years after the child is born)
• children who are born to mothers who have emigrated from a country where hepatitis B is widespread such as southeast Asia and China
• individuals who live in households where another member is infected with the virus
• infection through intravenous (IV) drug use and/or unprotected heterosexual or homosexual sexual contact
• infection through blood transfusions from infected donors

Demographics

Worldwide there are 450 million carriers of hepatitis B, 50 million of which are in Africa. Carriage rates vary markedly in different areas. In South Africa, infection is much more common in rural communities than in the cities.

According to the Centers for Disease Control (CDC), an estimated 78,000 persons in the United States were infected with HBV in 2001. People of all ages get hepatitis B, and about 5,000 die per year of sickness caused by HBV. An estimated 1.25 million Americans are chronically infected, of whom 20 to 30 percent acquired their infection in childhood. It is estimated that hepatitis B accounts for 20 to 25 percent of all acute viral hepatitis in children. Infected newborns rarely suffer but have 90 percent chance of becoming carriers. Twenty-five percent of all HAV positive newborns develop chronic liver disease by the third to fourth decade of life.

Causes and symptoms

Hepatitis B is caused by HBV, also called Hepadna virus. The virus has an incubation period of two to five months. It replicates in the liver, and virus particles are shed in large amounts into the blood. The blood of infected individuals is thus highly infectious.

Hepatitis B has a wide range of symptoms. It can also be mild, without symptoms. When present, the symptoms are non-specific and usually include fever, tiredness, loss of appetite, nausea, abdominal discomfort, dark urine, clay-colored bowel movements, and jaundice (yellowing of the skin and eyes).

When to call the doctor

Parents should call the doctor immediately if any of the following occurs:

• A child has changes in symptoms, is confused, is difficult to wake up, is lethargic (sluggish), or irritable.
• A child is unable to drink fluids.
• A child's skin becomes much more yellow in color.
• A child has signs of dehydration such as no urine in over eight hours or a dry mouth.
• A child starts to look very sick.

Diagnosis

A blood test is required to diagnose hepatitis B. The test detects one of the viral antigens called hepatitis B surface antigen (HBsAg) in the blood. Later on, HBsAg may no longer be present, in which case a test for antibodies to a different antigen, called hepatitis B core antigen, is used. If HBsAg can be detected in the blood for longer than six months, chronic hepatitis B is diagnosed.

Treatment

There is no cure for hepatitis B and no specific treatment is available. However, the following guidelines are often recommended:

• Fluids and diet. The best treatment is to ensure that the child drinks a lot of fluids and eats well.
• Rest. The child should rest while he or she has fever or jaundice. When fever and jaundice are gone, activity may be gradually increased as with the healthcare provider's approval.
• Medications. There is no medicine that gets rid of HBV or heals the liver. There are medications available to treat chronic HBV-infection. These work for some people, but experience with children is limited. Three drugs are licensed, as of 2004, for the treatment of chronic hepatitis B: Adefovir dipivoxil, alpha interferon, and lamivudine.