Mary D. Nettleman, MD, MS, MACP is the Chair of the Department of Medicine at Michigan State University. She is a graduate of Vanderbilt Medical School, and completed her residency in Internal Medicine and a fellowship in Infectious Diseases at Indiana University.
Jay W. Marks, MD, is a board-certified internist and gastroenterologist. He graduated from Yale University School of Medicine and trained in internal medicine and gastroenterology at UCLA/Cedars-Sinai Medical Center in Los Angeles.
New agents are under development to treat hepatitis B. Many of these are
nucleoside/nucleotide analogues that investigators hope will be more effective
than older agents. Experts also are working on treatment guidelines and the use
of multi-drug therapy. Vaccination remains the key to preventing hepatitis B and
holds the most promise for reducing disease burden.
Hepatitis B At A Glance
The hepatitis B virus is a DNA virus belonging to the Hepadnaviridae family
of viruses. Hepatitis B virus is not related to the hepatitis A virus or the
hepatitis C virus.
Some people with hepatitis B never clear the virus and are chronically
infected. Approximately 350 million individuals in the world and one million in
the United States are chronically infected with hepatitis B. Many of these
people appear healthy but can spread the virus to others.
Hepatitis B infection is transmitted through sexual contact, contact with
contaminated blood (for example, through shared needles used for illicit,
intravenous drugs), and from mother to child. Hepatitis B is not spread through
food, water, or casual contact.
Serologic (blood) markers specifically for hepatitis B virus are used to
diagnose hepatitis B viral infection. The blood tests can also identify people
who are at highest risk for complications.
Injury to the liver by hepatitis B virus is caused by the body's immune
response as the body attempts to eliminate the virus.
In the United States, 95% of adults who get hepatitis B are able to clear
the virus and cure themselves of infection. The remaining 5% of adults with
acute hepatitis B go on to develop chronic hepatitis B. Those who acquire the
infection in childhood are much more likely to have chronic infection. Chronic
hepatitis B may lead to cirrhosis or liver failure. Approximately 15% to 25% of
persons with chronic infection will die prematurely as a result of the
Progression of chronic hepatitis B viral infection occurs insidiously
(subtly and gradually), usually over several decades. The course is determined
primarily by the age at which the hepatitis B viral infection is acquired and
the interaction between the virus and the body's immune system.
Treatment with interferons or nucleoside/nucleotide analogues suppresses
viral reproduction in about 40% to 90% of patients with chronic hepatitis B. The
medications are also effective in reducing inflammation and improving blood
tests. This can delay or reduce complications such as cirrhosis. However, most
people do not have a permanent response and relapse is common. The medications
do not cure the infection.
Liver transplantation should be considered for patients with impending
liver failure due to acute (initial) infection or advanced cirrhosis.
Hepatitis B is preventable through vaccination. All children should receive
the vaccine. In addition, adults at high risk for hepatitis B should be
vaccinated. Unvaccinated people who are exposed to hepatitis B should be
evaluated by a physician to determine if they need specific immune globulin
Reference: Centers for Disease Control and Prevention, "Viral Hepatitis FAQs
for the Public," January 15, 2009