About Hepatitis B
More than 350 million people worldwide have chronic hepatitis B. In the United States, the prevalence is most common in people who were born in Africa, Asia, Middle East, Caribbean, Latin America and Eastern Europe. In the United States, reported case of Hepatitis B is mainly common among Asian Americans and even more increasingly and alarmingly, among African Americans, especially immigrants from Africa. These are populations that already experience health disparities and are underserved.
According to the WHO:
• Hepatitis B is a viral infection that attacks the liver and can cause both acute and chronic disease.
• The virus is transmitted through contact with the blood or other body fluids of an infected person.
• Two billion people worldwide have been infected with the virus and about 600 000 people die every year due to the consequences of hepatitis B.
• The hepatitis B virus is 50 to 100 times more infectious than HIV.
• Hepatitis B is an important occupational hazard for health workers.
• Hepatitis B is preventable with the currently available safe and effective vaccine.
Hepatitis B is a potentially life-threatening liver infection caused by the hepatitis B virus. It is a major global health problem and the most serious type of viral hepatitis. It can cause chronic liver disease and puts people at high risk of death from cirrhosis of the liver and liver cancer.
Worldwide, an estimated two billion people have been infected with the hepatitis B virus and more than 240 million have chronic (long-term) liver infections. About 600 000 people die every year due to the acute or chronic consequences of hepatitis B.
A vaccine against hepatitis B has been available since 1982. Hepatitis B vaccine is 95% effective in preventing infection and its chronic consequences, and is the first vaccine against a major human cancer.
Hepatitis B virus is transmitted between people by direct blood-to-blood contact or semen and vaginal fluid of an infected person. Modes of transmission are the same as those for the human immunodeficiency virus (HIV), but the hepatitis B virus is 50 to 100 times more infectious. Unlike HIV, the hepatitis B virus can survive outside the body for at least seven 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.
In developing countries, common modes of transmission are:
• Perinatal (from mother to baby at birth)
• Early childhood infections:
• (inapparent infection through close interpersonal contact with infected household contacts)
• Unsafe injection practices
• Unsafe blood transfusions
• Unprotected sexual contact.
The hepatitis B virus is not spread by contaminated food or water, and cannot be spread casually in the workplace.
The incubation period of the hepatitis B virus is 90 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.
Who is at risk for chronic disease?
The likelihood that infection with the hepatitis B virus becomes chronic depends upon the age at which a person becomes infected. Young children who become infected with the hepatitis B virus are the most likely to develop chronic infections:
• 90% of infants infected during the first year of life develop chronic infections;
• 30–50% of children infected between one to four years of age develop chronic infections.
• 25% of adults who become chronically infected during childhood die from hepatitis B-related liver cancer or cirrhosis
• 90% of healthy adults who are infected with the hepatitis B virus will recover and be completely rid of the virus within six months.
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 diarrhoea.
Some people with chronic hepatitis B can be treated with drugs, including interferon and antiviral agents. Treatment can cost thousands of dollars per year and is not available to most people in developing countries.
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.