Hepatitis B

About This Disease

Hepatitis B is a contagious liver disease caused by the hepatitis B virus. Hepatitis B can be either “acute” or “chronic:”

  • Acute Hepatitis B: a short-term illness that occurs within the first 6 months after someone is exposed to the Hepatitis B virus. Acute infection can, but does not always, lead to chronic infection.
  • Chronic Hepatitis B: a long-term illness that occurs when the Hepatitis B virus remains in a person’s body. The chance of developing a chronic infection depends on the age when a person becomes infected. Up to 90% of infants infected with the Hepatitis B virus will develop a chronic infection. In contrast, about 5% of adults will develop chronic Hepatitis B. Over time, as many as 1 in 4 people with chronic Hepatitis B can develop serious health problems, including liver damage, cirrhosis (scarring of the liver), liver cancer, and even death.

Signs and Symptoms

Although a majority of older children and adults (70%) develop symptoms from acute Hepatitis B infection, many young children below the age of 5 years do not. If symptoms occur, they can include:

  • Fever
  • Feeling tired
  • Loss of appetite
  • Nausea
  • Vomiting
  • Abdominal pain
  • Dark urine
  • Clay-colored bowel movements
  • Joint pain
  • Jaundice (yellow color in the skin or the eyes)

On average, symptoms appear 3 months after exposure, but they can appear any time between 6 weeks and 6 months after exposure. Symptoms usually last a few weeks, but some people can be ill for as long as 6 months.

While some people have ongoing symptoms similar to acute Hepatitis B, most individuals with chronic Hepatitis B remain symptom free for as long as 20 to 30 years. However, liver damage from the disease can take place during this time.


Hepatitis B virus is spread when blood, semen, or other body fluids infected with the virus enters the body of a person who is not infected. Chronically-infected people can spread Hepatitis B virus to others, even if they do not feel or look sick themselves.

The Hepatitis B virus is passed easily through breaks in the skin or in soft tissues such as the nose, mouth, and eyes. People can become infected during activities such as:

  • Birth (spread from an infected mother to her baby during birth)
  • Sex with an infected partner
  • Sharing needles, syringes, or other drug-injection equipment
  • Sharing items such as razors or toothbrushes with an infected person
  • Direct contact with the blood or open sores of an infected person
  • Exposure to blood from needle sticks or other sharp instruments

Hepatitis B virus can survive outside of the body on objects for at least 7 days. During that time, the virus can still cause infection if it enters the body of a person who is not infected.

Hepatitis B virus is not spread through food or water, sharing eating utensils, breastfeeding, hugging, kissing, hand holding, coughing, or sneezing.


Hepatitis B is diagnosed by one or more blood tests. These tests can help determine if a person:

  • Has acute or chronic infection
  • Has recovered from infection
  • Is immune to Hepatitis B
  • Could benefit from vaccination (has never been infected)

Only a health care professional can interpret individual test results.

The following persons should be tested for Hepatitis B to help determine the next best steps for vaccination or medical care:

  • All pregnant women
  • Household and sexual contacts of people with Hepatitis B
  • People born in certain parts of the world that have increased rates of Hepatitis B
  • People with certain medical conditions
  • People who inject drugs
  • Men who have sex with men
  • Incarcerated persons
  • Infants born to mothers infected with Hepatitis B


There is no medication available to treat acute Hepatitis B. During this short-term infection, doctors usually recommend rest, adequate nutrition, and fluids, although some people may need to be hospitalized.

Persons with chronic disease should see a doctor with experience in treating Hepatitis B infections. Those with chronic Hepatitis B should be monitored regularly for signs of liver disease and evaluated for possible treatment to slow down or prevent the effects of liver disease.


The best way to prevent Hepatitis B is by getting vaccinated. Hepatitis B vaccine is usually given as a series of 3 shots over a 6-month period. The entire series is needed for long-term protection. After receiving all three doses, Hepatitis B vaccine provides greater than 90% protection to infants, children, and young adults immunized before being exposed to the virus.

Hepatitis B vaccination is recommended for:

  • All infants, starting with the first dose of Hepatitis B vaccine at birth
  • All children and adolescents younger than age 19 years who have not been vaccinated
  • People who are at greater risk for Hepatitis B infection:
    • Have sex with an infected person
    • Have multiple sex partners
    • Have a sexually transmitted disease
    • Are men who have sexual contact with other men
    • Inject drugs or share needles, syringes, or other drug equipment
    • Live with a person who has chronic Hepatitis B
    • Are exposed to blood on the job (e.g., health care and public safety workers)
    • Are hemodialysis patients
    • Are residents or staff of facilities for developmentally disabled persons
    • Travel to countries with moderate or high rates of Hepatitis B
  • People with chronic liver disease
  • People with HIV infection
  • Anyone who wishes to be protected from Hepatitis B infection

An unvaccinated person who may have been exposed to the Hepatitis B virus should contact a health care provider immediately. If a person who has been exposed to Hepatitis B virus receives the Hepatitis B vaccine and/or a shot called “HBIG” (Hepatitis B immune globulin) within 24 hours, infection may be prevented.

Infants born to mothers infected with hepatitis B should receive HBIG. HBIG gives baby a “boost” or extra help to fight the virus and works best when given within the first 12 hours of life. The baby will also need to complete the full hepatitis B vaccination series for best protection.