Hepatitis B is one of the most common serious liver infections in the United States. In 2016, the Centers for Disease Control and Prevention reported that 862,000 Americans live with hepatitis B.

What Is Hepatitis B?

Hepatitis B is one of five main types of viral hepatitis, lettered from A to E, with a different virus responsible for each type. Hepatitis B causes inflammation, or swelling, in the liver that can result in liver damage, liver disease and other health problems.

For some people, hepatitis B is a short-term, or acute, illness that goes away in a few weeks or months. For others, it’s a chronic infection that lasts for years or even decades and can cause long-term health problems.

Causes of Hepatitis B

Hepatitis B is caused by the hepatitis B virus (HBV), which is transmitted through body fluids including blood and semen. The primary way HBV infection is passed from an infected person to others include:

• contact with contaminated blood or other body fluids
• mother-to-child transmission during birth
• non-sexual person-to-person contact, such as child-to-child
• sexual activity

Signs and Symptoms of Hepatitis B

Acute hepatitis B frequently does not cause any symptoms. A person’s immune system successfully fights off HBV and the person recovers, usually within three months. When symptoms do occur, they can range from mild to severe and may include:

• abdominal pain
• dark urine
• fatigue and weakness
• fever
• jaundice, or a yellowing of skin and eyes
• joint and muscle pain
• loss of appetite
• nausea and vomiting

When HBV lingers in the body for six months or longer, it is considered a chronic infection. As chronic hepatitis B progresses symptoms of cirrhosis and liver failure can develop, including:

• easy bleeding and bruising
• enlarged spleen
• fluid accumulation in the abdomen
• internal bleeding due to enlarged or swollen abdominal veins
• itchy skin

In addition, people with hepatitis B are at increased risk of developing a liver cancer called hepatocellular carcinoma.

How Is Hepatitis B Diagnosed?

• Blood tests can detect HBV in the body and determine if infection is acute or chronic.
• Imaging procedures such as ultrasound elastography may be used to measure the liver’s stiffness, size and shape, and monitor blood flow through the liver.
• Liver biopsy can confirm a diagnosis of hepatitis B as well as detect the severity of liver damage.

Prevention of Hepatitis B

The HBV vaccine is the most effective way to limit the spread of HBV. For unvaccinated people exposed to HBV, an injection of the vaccine along with hepatitis B immune globulin, or HBIG, is often recommended within 24 hours of exposure. 

Other HBV prevention strategies include:

• not receiving tattoos or body piercings in unsterile conditions
• not sharing personal items such as razors, toothbrushes, nail clippers and body jewelry
• not sharing needles or other drug equipment
• practicing safe sex
• washing hands thoroughly after any blood exposure and using bleach to clean up any spilled blood

Treatments for Hepatitis B

Many cases of acute hepatitis B clear up on their own and may not require any treatment.

Currently, there is no cure for chronic hepatitis B or a medical therapy that completely clears HBV from the body. Treatment can slow disease progress, prevent complications, including cirrhosis and reduce the risk of liver cancer. Options may include:

• antiviral drugs such as tenofovir disoproxil fumarate, tenofovir alafenamide and entecavir, which slow down or stop HBV and reduce inflammation and damage to the liver
• immunomodulator drugs such as interferon alfa-2b and pegylated interferon, which boost the immune system’s ability to fight HBV