Causes and Diagnoses

Causes and Diagnoses of Hepatitis B

Hepatitis B is caused by infection with the hepatitis B virus. It is spread through contact with an infected person’s bodily fluids. The infected fluids include:

  • Blood
  • Saliva
  • Semen
  • Vaginal secretions

The virus is commonly spread through sharing drug supplies, razors and toothbrushes; accidental needle sticks and unprotected sex with an infected partner.

Diagnosing hepatitis B

Hepatitis B can be diagnosed with a physical exam, discussion of your symptoms and blood test. If the infection appears to be chronic, your physician may order:

  • Liver biopsy: A small sample of the liver tissue is removed with a needle for analysis under a microscope.
  • Ultrasound: This is a quick and easy diagnostic technique that uses high-frequency sound waves to create images of the organs and systems within the body. An ultrasound can determine the extent of liver disease.

Preventing the spread of hepatitis B

There are ways to minimize your risk of getting hepatitis B, including:

  • Get the three-part vaccine if you are under 18 or at risk for HBV.
  • Use a condom every time you have sex.
  • Get tattoos and body piercings from trusted sources.
  • Don’t share needles and drug supplies.
  • Don’t share toothbrushes or razors.
  • Don’t touch someone else’s bodily fluids except when wearing gloves.

Diagnostic Tests


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