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Hepatitis B is a contagious, acute disease of the liver that may become chronic. The Centers for Disease Control and Prevention estimates that nearly 43,000 people contracted hepatitis B in the United States in 2007, although the number of reported cases is much lower because some people do not show symptoms. There are an estimated 800,000 to 1.4 million chronic cases in the United States. Globally, there are about 360 million chronically infected people, and as many as 626,000 people die of hepatitis B every year.
Acute hepatitis B is caused by the hepatitis B virus, which is found in certain body fluids of infected people. Chronic, or lifelong, hepatitis B is caused when the virus remains in the body beyond the acute stage.
Hepatitis B virus can be found in the blood, semen, vaginal fluids, and other body fluids of infected people. Transmission happens when infected body fluids enter another person's body. The virus is most commonly transmitted in the following ways:
Hepatitis B is not transmitted through shaking hands, coughing, sneezing, breastfeeding, or sharing cups and utensils.
Hepatitis B does not always cause obvious symptoms. Children are less likely than adults to have symptoms, but they are more likely than adults to develop chronic hepatitis B after an acute infection.
Symptoms of acute hepatitis B include
Symptoms of acute hepatitis B generally appear three months after you have been exposed to the virus and may last for several weeks to six months.
People with chronic hepatitis B may show no symptoms for two to three decades. However, about 15 to 25 percent of those chronically infected may develop serious liver disease that is not apparent at first. Chronic infection can ultimately lead to long-term liver damage, liver cancer, or liver failure—all of which can be fatal.
Healthcare providers review symptoms and can diagnose hepatitis B with a blood test or a combination of blood tests, which will reveal the presence of hepatitis B virus or antibodies to it.
There are no medicines for treating acute hepatitis B infection after you get it. If you have a mild case, your healthcare provider probably will prescribe rest, plenty of fluids, and a nutritious diet. While your body fights hepatitis B, you should avoid any medicines—over-the-counter or prescribed—that could damage your liver. You also should avoid alcohol during your recovery period, as alcohol may also damage your liver.
Chronic hepatitis B can be treated with certain medicines, but most people will not have complications severe enough to require medicine. Those with active liver disease may be prescribed one of several medicines to prevent liver damage. If you show no signs of liver damage, your healthcare provider will monitor you to look for liver disease, should it occur.
The best way to prevent hepatitis B is to be vaccinated. The hepatitis B vaccine is usually given in a series of three or four shots given over a six-month period. The vaccine is safe for adults and children and is routinely given to infants at birth.
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Last Updated October 02, 2009