What is hepatitis B (HBV)?
Hepatitis B is a virus that causes inflammation of the liver. Chronic (long-lasting) hepatitis B can cause liver cell damage, which can lead to cirrhosis (scarring of the liver) and cancer. It is estimated that 5,000 people die each year in the United States due to the complications of cirrhosis and liver cancer as a result of HBV.
How common is it?
According to Centers for Disease Control and Prevention (CDC), it is estimated that 1.25 million people in the United States have chronic HBV. There were an estimated 73,000 new HBV infections in the United States in 2003.
How is it transmitted?
HBV is transmitted through direct contact with blood, semen, or vaginal secretions.
Hepatitis B can be transmitted through unprotected vaginal, anal, or oral sex. In adolescents and adults, this is the most common mode of transmission.
HBV can also be transmitted by injecting drug users who share needles or other injecting equipment contaminated with HBV-infected blood.
Although tattoo, body piercing, and acupuncture needles may transmit HBV, these exposures account for only a small proportion of reported cases in the United States.
Mothers who have HBV can pass it on to their babies during birth.
Although rarely, transmission may occur in the following ways.
Saliva can be a means of transmission through bites. However, transmission has not been documented to occur as a result of other types of exposure to saliva, including kissing.
The risk of transmission from blood transfusion is currently low in the U.S. since blood banks screen all donated blood.
HBV is found in transmittable levels in body fluids including:
Semen
Vaginal secretions
Saliva
Blood
HBV has also been found in low concentrations in other body fluids, though these fluids have NOT been associated with transmission:
Tears
Urine
Feces
Breast milk
Cerebrospinal fluid
HBV is not spread through food or water or by casual contact.
Symptoms
Many adults have few or no symptoms. Symptoms may mimic the flu and can include:
Loss of appetite
Malaise (feeling of ill-health)
Fatigue (feeling tired all the time)
Nausea and vomiting
Abdominal pain
Dark urine
Jaundice (yellowing of the skin and eyes)
Rash or arthritis may occur prior to the onset of other symptoms (during the prodromal or early acute stage).
A few patients (1%) have a more severe course of illness and may experience sudden and severe liver failure within a short period of time after infection. These people may suddenly collapse with fatigue, have jaundice, and develop swelling in their abdomen. This can be fatal if not treated immediately.
Testing/Diagnosis
Your health care provider can confirm HBV by using a special blood test to detect HBV particles or antibodies in the blood. Blood tests can determine whether a person has acute or chronic hepatitis.
HBV is not usually included in routine blood tests, so patients may have to request the test from their health care provider. There are three standard blood tests for HBV:
HBsAg (looks for hepatitis B surface antigens): This test detects the presence and levels of virus in the blood. When this test is positive or reactive, it means that the person is infected with HBV at the present time and can pass the virus to others.
Anti-HBs (looks for antibody to the hepatitis B surface antigen): If this test is positive or reactive, it means that the person is immune, either as a result of having had the disease previously or from receiving the hepatitis B vaccine. This person cannot pass the virus to others.
Anti-HBc (antibody to hepatitis B core antigen): This is usually present in chronic carriers, who can pass the virus to others. However, if it is present with a positive anti-HBs test, then it is associated with recovery from a previous infection, and this person is not a carrier.
In many settings, a health care provider will run all 3 of the above tests and interpret the results based on the outcome of all 3.
HBV usually takes between 3 weeks to 2 months to show up in the blood. It may take up to two months after infection for a Hepatitis B test to be accurate.
If chronic HBV is suspected, other tests may be ordered. These test can help to decide treatment options and may include:
Ultrasound, which tests for signs of liver damage and cancer
Liver biopsy, to detect signs of liver damage and cancer
Liver function tests, which tests to see if enzymes are higher than normal levels, which indicates damage to liver cells.
E-antigen test, which detects e-antigen, a viral protein that is put out by HBV-infected cells. This test is often used to monitor the effectiveness of some HBV therapies.
After receiving the hepatitis B vaccine, the following people may benefit from antibody confirmatory testing in order to be sure the vaccine is working. The test should be performed within 2 months after completion of the series or it may not give accurate results.
A person whose sex partner has chronic hepatitis B.
A person whose immune system is compromised (for instance, if someone living with AIDS).
A person whose job exposes him or her to human blood.
A child who is born to an HBV-positive mother.
Babies born to infected mothers should get two anti-HBs tests at aged 9 to 15 months to be certain that they are making antibodies, a sign that the vaccine has worked well. (Babies of HBV-infected mothers are not tested at birth but are automatically given the HBIG and the first shot of the hepatitis B vaccine series.)
Treatment
Treatment considerations for HBV vary depending on whether the infection is acute or chronic. Always consult your health care provider for specific recommendations and treatment options.
Acute (newly acquired):
No specific treatment is available for acute HBV infection.
Most patients with acute viral hepatitis experience a self-limited illness (one that runs a defined, limited course), and go on to recover completely.
There is no accepted therapy and no restrictions on diet or activity.
In most cases, hospitalization should be avoided, to prevent spread of the virus to other patients. It should, however, be considered for patients who are severely ill.
Your health care provider can recommend the best options based on your individual needs for care.
Chronic (persistent):
Interferon is used to help stop the replication of HBV. It is called an antiviral agent. Interferon has been 40 percent effective in eliminating chronic HBV infection. Persons who became infected during adulthood were most likely to respond to this treatment. Long-term follow up of treated patients suggests that remission of chronic HBV from treatments with interferon is of long duration. Talk to your health care provider about the use of Interferon.
Lamivudine (Epivir) is now available to treat chronic HBV. It is the first medication specifically formulated to do so. Talk to your health care provider for more information about lamivudine and to learn if it is right for you.
Adefovir dipivoxil (Hepsera™), is the first nucleotide analog approved to treat chronic HBV. Adefovir dipivoxil slows the progression of chronic HBV by interfering with the virus' replication process within the body. Results show that adefovir dipivoxil can significantly reduce liver inflammation and scarring. It has been shown to work in people who have resistance to the drug lamivudine. Consult your health care provider for more information about adefovir dipivoxil and to learn it is right for you.
Entecavir (Baraclude™) slows the progression of chronic hepatitis B by interfering with viral reproduction. In clinical studies, patients treated with entecavir showed significant improvement in the liver inflammation caused by HBV and an improvement in the degree of liver fibrosis (scarring). It is important to stay under your doctor’s care while taking entecavir. Baraclude™ was approved by the Food & Drug Administration (FDA) in March 2005. Talk to your doctor to learn more about this treatment.
Peginterferon (Pegasys®) is the first and only pegylated interferon approved for the treatment of chronic hepatitis B, including both variations of the virus. Peginterferon has a dual mode of action; it slows replication of the hepatitis B virus and boosts the immune system. Pegasys® was approved by the FDA to treat chronic hepatitis B in May 2005. Talk to your doctor to learn more about peginterferon.
What does it mean for my health?
Hepatitis B can cause:
Chronic infection
Cirrhosis (scarring) of the liver
Liver cancer
Death
The good news is that hepatitis B is preventable through vaccination. A person can choose to be vaccinated and no longer have to worry about being infected with HBV.
Reduce your risk
Vaccination before exposure to HAV:
Hepatitis B is preventable through vaccination. Since hepatitis D can only coexist with hepatitis B, getting vaccinated against hepatitis B also protects you against hepatitis D.
The HBV vaccine is given in a series of three doses.
The first and second doses must be given at least one month apart.
The first and third doses must be given at least 4 months apart.
If a dose is missed, it should be given as soon as possible.
The series should not be restarted if a dose is missed.
Routine booster doses of the HBV vaccine are NOT currently recommended.
Consult your health care provider for more information about the HBV vaccine and if it is right for you.
HIV can impair the response to the hepatitis vaccine.
A new combination vaccine called Twinrix has been approved for protection from both HAV and HBV in persons 18 and older. It reduces the total number of injections for vaccination from both viruses from five to three.
Hepatitis B vaccine has been recommended as a routine infant vaccination since 1991 and as a routine adolescent vaccination since 1995. It is recommended for everyone 18 years of age and younger and for adults over 18 who are at risk for HBV infection. (However, anyone seeking immunity from HBV may be vaccinated.) Vaccination against hepatitis B is recommended for those who are at high risk of infection, including:
Health care professionals
Clients/staff of institutions for the developmentally disabled
Sexually active men who have sex with men
Household/sexual contacts of chronic HBV carriers
Travelers to and immigrants from countries with high incidence of HBV
Sexually active heterosexual men and women, including: those in whom another STD was recently diagnosed (hepatitis B infection with an HIV infected individual is more likely to lead to chronic HBV); those who have had more than one sex partner in the preceding six months; those who have received treatment in an STD clinic; and, those who are sex workers or prostitutes
Injecting and non-injecting drug users
Hemodialysis patients
Recipients of certain blood products
Inmates of long-term correctional facilities.
Immune Globulin (IG) after exposure to HAV:
Post exposure treatment to prevent illness (Immune globulin and HBV vaccine); if a person is exposed to hepatitis B and has NOT been vaccinated before the exposure:
For unvaccinated individuals who have had recent exposure to someone with acute hepatitis B, a dose of hepatitis B immune globulin (HBIG) may prevent illness.
The hepatitis B vaccine given with HBIG is also recommended. (The hepatitis B vaccine in conjunction with HBIG is more effective than administering the hepatitis B vaccine alone.)
Both should be administered within 7 days after the exposure, as treatment is recommended even without testing.
Since 1985, all plasma units for preparation of immune globulin have been screened for HIV.
Sexual Prevention:
Abstinence and mutual monogamy between two uninfected partners also offer a high level of protection.
Latex condoms offer effective prevention during vaginal and anal sex by reducing contact with infected bodily fluids (semen, vaginal secretions and blood).
A non-lubricated latex condom can be used for mouth-to-penis contact. Household plastic wrap, dams or a latex condom cut lengthwise and opened flat can reduce the risk of transmission during mouth-to-vulva or oral-anal contact.
Non-Sexual Prevention:
Avoid contact with infected blood or other body fluids directly or on objects such as needles, razors, toothbrushes, etc.
Clean surfaces contaminated with blood or other body fluids with a solution of 1 part household bleach and 10 parts water.
Cover cuts, sores, and rashes with bandages.
Talk to your partner
If you have an acute or chronic hepatitis B infection, you should discuss it with your partner so that he or she can learn how to protect themselves from becoming infected with HBV.
Where can I get more information?
Centers for Disease Control (CDC):
Viral Hepatitis Division and National Immunization Program
Hepatitis Foundation International
American Liver Foundation
Immunization Action Coalition (IAC)
Parents of Kids with Infectious Diseases (PKID)
Share your story
Do you have an experience related to hepatitis B that you are willing to share with others? Triumphs? Challenges? Please send your story to mystory@ashastd.org.
ASHA sincerely appreciates every submission and each is confidential and anonymous. It is ASHA's intent to collect these comments for use in our patient advocacy work, including potential publication. All submissions are property of ASHA and can be edited for length and clarity. Due to the large volume of emails, we regret that we cannot provide a response to each submission.
Please note: This email service cannot answer questions about hepatitis B. For any questions, please contact your health care provider or call the CDC at (800) CDC-INFO.
Tuesday, March 10, 2009
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