Hepatitis B

Hepatitis B is a liver infection caused by the hepatitis B virus (HBV). Hepatitis B is transmitted when blood, semen, or another body fluid from a person infected with the hepatitis B virus enters the body of someone who is not infected. This can happen through sexual contact; sharing needles, syringes, or other drug-injection equipment; or from mother to baby at birth. The hepatitis B virus can survive outside the body 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.

For some people, hepatitis B is an acute, or short-term, illness but for others, it can become a long-term, chronic infection. About 2%–6% of adults and 90% of infected infants become chronically infected. Chronic hepatitis B can lead to serious health issues, like cirrhosis or liver cancer. The best way to prevent hepatitis B is by getting the hepatitis B vaccine. The hepatitis B vaccine is safe and effective and is usually given as 3 shots over a 6-month period. Although anyone can get hepatitis B, increased risk factors include:

  • Sex with an infected person
  • Multiple sex partners
  • Sexually transmitted diseases
  • Men who have sexual contact with other men
  • Injecting drugs or sharing needles, syringes, or other drug equipment
  • Living with a person who has hepatitis B
  • Infants born to infected mothers
  • Exposure to blood on the job
  • Hemodialysis patients
  • Travelers to countries with moderate to high rates of hepatitis B

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