Hepatitis B (patient information)
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Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: João André Alves Silva, M.D. [2]
Overview
Hepatitis B is irritation and swelling (inflammation) of the liver due to infection with the hepatitis B virus (HBV). It is a potentially life-threatening liver disease, considered a major global health problem. Symptoms may include: fever, fatigue, loss of appetite, nausea and vomiting, abdominal pain, and jaundince. It can cause both acute and chronic liver disease, and puts people at high risk of death from cirrhosis and liver cancer. The virus is transmitted through contact with the blood or other body fluids of an infected person. Hepatitis B is preventable with the currently available safe and effective vaccine. Complications may include: chronic hepatitis, cirrhosis, liver cancer and death.
What are the symptoms of Hepatitis B?
Most people do not experience any symptoms during the acute infection phase. After first becoming infected with the hepatitis B virus:
- You may have no symptoms
- You may feel sick for a period of days or weeks
- You may become very ill (called fulminant hepatitis)
If your body is able to fight off the hepatitis B, any symptoms that you had should go away over a period of weeks to months.
Some people's bodies are not able to completely get rid of the hepatitis B. This is called chronic hepatitis B. Many people who have chronic hepatitis B have few or no symptoms. They may not even look sick. As a result, they may not know they are infected. However, they can still spread the virus to other people. Symptoms may not appear for up to 6 months after the time of infection. Early symptoms may include:
- Appetite loss
- Abdominal pain
- Extreme fatigue
- Fever, low-grade
- Muscle and joint pain
- Nausea and vomiting
- Dark urine
- Yellowing of the skin and eyes (jaundice)
People with chronic hepatitis may have no symptoms, even though gradual liver damage may be occurring. Over time, some people may develop symptoms of chronic liver disease, cirrhosis, and liver cancer.
More than 90% of healthy adults who are infected with the hepatitis B virus will recover and be completely rid of the virus within 6 months.
What causes Hepatitis B?
Hepatitis B is caused by the hepatitis B virus (HBV).
In highly endemic areas, HBV is most commonly spread from mother to child at birth, or from person to person in early childhood.
Perinatal or early childhood transmission may also account for more than one third of chronic infections in areas of low endemicity, although in those settings, sexual transmission and the use of contaminated needles, especially among injecting drug users, are the major routes of infection.
The hepatitis B virus can survive outside the body for at least 7 days. During this time, the virus can still cause infection if it enters the body of a person who is not protected by the vaccine. The incubation period of the hepatitis B virus is 75 days on average, but can vary from 30 to 180 days. The virus may be detected 30 to 60 days after infection and persists for variable periods of time.
Hepatitis B infection can be spread through having contact with the blood, semen, vaginal fluids, and other body fluids of someone who already has a hepatitis B infection.
Ways of infection include:
- Blood transfusions (not common in the United States)
- Direct contact with blood in health care settings
- Sexual contact with an infected person
- Tattoo or acupuncture with unclean needles or instruments
- Shared needles during drug use
- Shared personal items (such as toothbrushes, razors, and nail clippers) with an infected person
The hepatitis B virus is not spread by contaminated food or water, and cannot be spread casually in the workplace.
Who is at highest risk?
The likelihood that infection with the hepatitis B virus becomes chronic depends upon the age at which a person becomes infected. Children less than 6 years of age who become infected with the hepatitis B virus are the most likely to develop chronic infections:
- 80–90% of infants infected during the first year of life develop chronic infections
- 30–50%% of children infected before the age of 6 years develop chronic infections
In adults:
- <5% of otherwise healthy adults who are infected will develop chronic infection
- 15–25% of adults who become chronically infected during childhood die from hepatitis B-related liver cancer or cirrhosis
Risk factors for hepatitis B infection include:
- Being born, or having parents who were born in regions with high infection rates (including Asia, Africa, and the Caribbean)
- Being infected with HIV
- Being on hemodialysis
- Having multiple sex partners
- Men having sex with men
Most of the damage from the hepatitis B virus occurs because of the way the body responds to the infection. When the body's immune system detects the infection, it sends out special cells to fight it off. However, these disease-fighting cells can lead to liver inflammation.
When to seek urgent medical care?
Call your health care provider if:
- You develop symptoms of hepatitis B
- Hepatitis B symptoms do not go away in 2 or 3 weeks, or new symptoms develop
- You belong to a high-risk group for hepatitis B and have not yet received the Hepatitis B vaccine.
Diagnosis
It is not possible, on clinical grounds, to differentiate hepatitis B from hepatitis caused by other viral agents and, hence, laboratory confirmation of the diagnosis is essential. A number of blood tests are available to diagnose and monitor people with hepatitis B. They can be used to distinguish acute and chronic infections.
Laboratory diagnosis of hepatitis B infection focuses on the detection of the hepatitis B surface antigen HBsAg. WHO recommends that all blood donations are tested for this marker to avoid transmission to recipients.
The following tests are done to identify and monitor liver damage from hepatitis B:
- Acute HBV infection is characterized by:
- Presence of HBsAg
- Presence of immunoglobulin M (IgM) antibody to the core antigen, HBcAg
- During the initial phase of infection, patients are also seropositive for HBeAg.
- Chronic infection is characterized by:
- Persistence (>6 months) of HBsAg (with or without concurrent HBeAg)
- Persistence of HBsAg is the principal marker of risk for developing chronic liver disease and hepatocellullar carcinoma (HCC) later in life
- The presence of HBeAg indicates that the blood and body fluids of the infected individual are highly contagious
The following tests are done to help diagnose and monitor people with hepatitis B:
- Antibody to HBsAg (Anti-HBs) -- a positive result means you have either had hepatitis B in the past, or have received a hepatitis B vaccine
- Antibody to hepatitis B core antigen (Anti-HBc) -- a positive result means you had a recent infection or an infection in the past
- Hepatitis B surface antigen (HBsAg) -- a positive result means you have an active infection
- Hepatitis E surface antigen (HBeAg) -- a positive result means you have a hepatitis B infection and are more likely to spread the infection to others through sexual contact or sharing needles
Patients with chronic hepatitis will need ongoing blood tests to monitor their status.
Treatment options
There is no specific treatment for acute hepatitis B. Care is aimed at maintaining comfort and adequate nutritional balance, including replacement of fluids that are lost from vomiting and diarrhea.
Acute hepatitis needs no treatment other than careful monitoring of liver and other body functions with blood tests. You should get plenty of bed rest, drink plenty of fluids, and eat healthy foods. In the rare case that you develop liver failure, you may need a liver transplant. A liver transplant is the only cure in some cases of liver failure.
People with chronic hepatitis B who require treatment, can be given drugs, including:
- Oral antiviral agents, such as:
- Tenofovir
- Entecavir
- Interferon injections
These medications can decrease or remove hepatitis B from the blood and reduce the risk of cirrhosis and liver cancer. Treatment can slow the progression of cirrhosis, reduce incidence of HCC and improve long term survival. Treatment, however, is not readily accessible in many resource-constrained settings.
Liver transplantation is used to treat severe, chronic hepatitis B liver disease.
Patients with chronic hepatitis should avoid alcohol and should always check with their doctor or nurse before taking any over-the-counter medications or herbal supplements. This even includes medications such as acetaminophen, aspirin, or ibuprofen.
Where to find medical care for Hepatitis B?
Directions to Hospitals Treating Hepatitis B
Prevention
The hepatitis B vaccine is the mainstay of hepatitis B prevention. WHO recommends that all infants receive the hepatitis B vaccine as soon as possible after birth, preferably within 24 hours.
The birth dose should be followed by 2 or 3 doses to complete the primary series.
In most cases, 1 of the following 2 options is considered appropriate:
- A 3-dose schedule of hepatitis B vaccine, with the first dose (monovalent) being given at birth and the second and third (monovalent or combined vaccine) given at the same time as the first and third doses of DTP vaccine
- 4 doses, where a monovalent birth dose is followed by 3 monovalent or combined vaccine doses, usually given with other routine infant vaccines
The complete vaccine series induces protective antibody levels in more than 95% of infants, children and young adults. Protection lasts at least 20 years and is possibly lifelong.
All children and adolescents younger than 18 years old and not previously vaccinated should receive the vaccine if they live in countries where there is low or intermediate endemicity. In those settings it is possible that more people in high risk groups may acquire the infection and they should also be vaccinated. They include:
- People who frequently require blood or blood products, dialysis patients, recipients of solid organ transplantations
- People interned in prisons
- Injecting drug users
- Household and sexual contacts of people with chronic HBV infection
- People with multiple sexual partners, as well as health-care workers and others who may be exposed to blood and blood products through their work
- Travellers who have not completed their hepatitis B vaccination series should be offered the vaccine before leaving for endemic areas
Screening of all donated blood has reduced the chance of getting hepatitis B from a blood transfusion.
Mandatory reporting of the disease allows state health care workers to track people who have been exposed to the virus. The vaccine is given to those who have not yet developed the disease.
The hepatitis B vaccine or a hepatitis B immune globulin (HBIG) shot may help prevent hepatitis B infection if it is given within 24 hours of exposure.
Lifestyle measures for preventing transmission of hepatitis B:
- Avoid sexual contact with a person who has acute or chronic hepatitis B
- Use a condom and practice safe sex
- Avoid sharing personal items, such as razors or toothbrushes.
- Do not share drug needles or other drug equipment (such as straws for snorting drugs)
- Clean blood spills with a solution containing 1 part household bleach to 10 parts water
Hepatitis B (and hepatitis C) viruses cannot be spread by casual contact, such as holding hands, sharing eating utensils or drinking glasses, breast-feeding, kissing, hugging, coughing, or sneezing.
What to expect (Outlook/Prognosis)?
The acute illness usually goes away after 2 - 3 weeks. The liver usually returns to normal within 4 - 6 months in almost all patients who are infected. Some people develop chronic hepatitis.
- Almost all newborns and about 50% of children who become infected with hepatitis B develop chronic hepatitis. Less than 5% of adults who are infected with the hepatitis B virus develop the chronic condition.
- Chronic hepatitis B infection increases the risk for liver damage, including cirrhosis and liver cancer.
- People who have chronic hepatitis B can transmit the infection. They are considered carriers of the disease, even if they do not have any symptoms.
Liver cancer is almost always fatal and often develops in people at an age when they are most productive and have family responsibilities.
In developing countries, most people with liver cancer die within months of diagnosis. In high-income countries, surgery and chemotherapy can prolong life for up to a few years.
Possible complications
There is a much higher rate of hepatocellular carcinoma in people who have chronic hepatitis B than in the general population. Other complications may include:
- Chronic persistent hepatitis
- Cirrhosis
- Fulminant hepatitis, which can lead to liver failure and possibly death
Sources
http://www.nlm.nih.gov/medlineplus/ency/article/000279.htm World Health Organization Template:WSTemplate:WH