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About Hepatitis B

Hepatitis B is:

People of Asian Descent: Get Tested

Two thirds of the 400 million people in the world who have a chronic hepatitis B are from Asia. If you or your parents emigrated to the U.S. from Asia – get tested!

  • A "silent disease." It can live in your body for 50+ years before you have symptoms.
  • Responsible for 80 percent of all liver cancer in the world.
  • Harder to fight off the younger you are; 90 percent of babies will go on to develop a chronic infection compared to 5 to 10 percent of adults.
  • 100 times more contagious than AIDS.
  • Responsible for approximately 600,000 deaths worldwide each year.

According to the World Health Organization (WHO) nearly 400 million people worldwide have chronic hepatitis B, and 1.25 million of these people are in the U.S.

Fortunately, the virus can be prevented with the hepatitis B vaccine.

A Dangerous Disease

A chronic hepatitis B infection can go undetected for years – even decades in many cases. The longer a hepatitis B infection is left untreated, the more susceptible you are to developing severe scarring of the liver (cirrhosis) and liver cancer.

How do you get it?

The hepatitis B virus is transmitted when an infected person’s blood or body fluids (e.g., saliva, semen) enters your bloodstream.

Common Misconceptions

Hepatitis B is not a genetic disease. Also, it cannot be transmitted:

  • Through food or water
  • By hugging
  • Through sneezing or coughing

Ways hepatitis B is spread:

  • Sharing IV needles
  • Unprotected sex
  • Sharing razors or toothbrushes
  • From mother to newborn during the delivery process

In the U.S., hepatitis B is spread primarily through sexual transmission and contaminated needles. In other areas of the world (e.g., Asia) hepatitis B is spread through birth.

Acute vs. Chronic Infection

A hepatitis B infection can be temporary (acute) or long-lasting (chronic).

bullet Frequently asked questions about hepatitis B


Known as a silent infection, nearly 70 percent of people who first become infected with hepatitis B do not have symptoms.

Severe Symptoms

Symptoms such as yellow skin, swollen stomach and severe vomiting require immediate medical attention.

The other 30 percent of people may experience:

  • Fever
  • Fatigue
  • Joint pain
  • Nausea
  • Loss of appetite
  • Dark urine


A hepatitis viral panel (series of blood tests) is used to diagnose a hepatitis B infection. These blood test also establish if the infection is acute or chronic.

These tests are looking for the presence of HBsAg (hepatitis B surface antigen), a protein found on the surface of hepatitis B. The presence of HBsAg indicates a current hepatitis B infection.

Liver Damage

If you have a chronic infection, your doctor may check for liver damage with a liver function test (LFT).

Acute hepatitis B: An acute infection is characterized by the presence of both HBsAg and immunoglobulin M (IgM). IgM is an antibody produced by your immune system.

Chronic hepatitis B: If IgM is not present, and HBsAg has been in your body for six months or longer, it is likely that the infection is chronic.

Hepatitis D Screening

If a hepatitis B infection is determined, you will then be tested for hepatitis D. Hepatitis D is prevalent in the Middle East, Central Asia, South Pacific islands and the Mediterranean Basin.

Hepatitis D is a serious liver disease found only in people with hepatitis B. A coinfection with hepatitis D can accelerate liver damage and worsen symptoms of hepatitis B.

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