Medical Resources:

We feel that education is an important resource to families, therefore, this month; we would like to provide you with the following information on Hepatitis B.

Hepatitis B

The hepatitis B virus (HBV) is a DNA virus and a member of the hepadna family of viruses, and is a very common virus with an estimated 300 million carriers worldwide.

The hepatitis B virus is a complex virus with a central core and a protein coat. A number of antigens are associated with this virus and each antigen may result in the production of a corresponding antibody. Some of these antigens and antibodies are detected in routine commercially available assays. Assays to detect the hepatitis B virus DNA are now also available.

When the hepatitis B virus infects the liver, it replicates and produces excess surface material, some of which reaches the blood. Only when there is a great deal of viral replication does a significant load of the virus reach the blood. When there is less viral replication, the virus core is only detected in the liver but not in the blood (when assayed by the routine commercially available tests). The marker for the surface is HBsAg (hepatitis B surface antigen) and the markers for the core are HBeAg (hepatitis B "e" antigen) and HBV-DNA.

There is a recently described mutant strain of HBV (pre-core mutant) in which the virus cannot manufacture HBeAg and thus the only marker for the presence of the virus core is HBV-DNA. These patients may have antibodies to HBeAg and often have very severe liver disease.

The presence of hepatitis B surface antigen (HBsAg) signifies infection with the virus but does not give any information concerning infectivity or the presence of ongoing liver damage. When the virus is cleared from an individual, the antibody to hepatitis B surface (anti-HBs) develops and confers immunity to further virus infection. Anti-HBs often remains for life.

Most individuals infected with hepatitis B virus will clear the virus with the development of anti-HBs. Only about five percent of people will not clear HBsAg and will not develop anti-HBs. Anti-HBc will remain positive in these patients.

HBsAg should be checked every year to see if a person is still a carrier. Less than 1% of carriers clear HBsAg and develop anti-HBs each year.

For additional information about the needs specific to our Waiting Children, Great Wall offers a Waiting Child medical glossary.  The glossary can be accessed through the following link: WC Medical Glossary

The U.S. National Library of Medicine and the National Institutes of Health also offer additional medical information and resources at: http://medlineplus.gov/