Hepatitis B virus (HBV)
As noted earlier, it is possible for a mother with hepatitis B to pass HBV on to her newborn. If your doctor suspects that your child may have hepatitis B, he or she may order a blood test to see whether your child’s blood contains a portion of the virus called the surface antigen.
If the surface antigen test comes back positive, your child’s doctor may run additional tests for other portions of the virus, ones that will tell how the virus is behaving within your child’s body (e.g., is it being cleared by the immune system, entering a latent phase, or rebounding/reactivating).
Children with chronic hepatitis B should be checked every six months to see how well their livers are functioning. If it appears that the virus is beginning to damage the liver, your doctor may recommend that your child have a liver biopsy to check the extent of the damage. The results of the biopsy will help determine whether the time is right to start treatment.
It is not uncommon for many members of a single family to be infected with HBV without knowing it. But because in the U.S. HBV is most often passed from mother to child, your doctor will also want to know whether there is any history of liver disease, and in particular liver cancer, in your family; this knowledge could help your doctor predict how the virus will behave within your child.
Also, you should talk with your doctor about having all members of your family tested for HBV, and about vaccinating all those whose test results come back negative (that is, who are not infected with the virus).