Hepatitis B Causes
A person gets hepatitis B through infection with the hepatitis B virus (also known as HBV). There are no other causes of hepatitis B. The disease cannot be spread through normal everyday activities, like kissing, hugging, or shaking hands. The virus is transmitted through infected bodily fluids, including blood and blood products, semen, and vaginal fluids.
What Causes Hepatitis B?There is only one cause of hepatitis B -- an infection with the hepatitis B virus (also known as HBV). The hepatitis B virus is a DNA virus that belongs to the genus Orthohepadnavirus of the Hepadnaviridae family.
When a person is infected with the hepatitis B virus, it is able to enter liver cells from the blood and then use those cells to make more copies of the virus. As more and more of the hepatitis B virus is made in the liver cells, the liver cells can become damaged and may even die.
A person infected with the hepatitis B virus may develop:
- A sudden onset of fever
- Extreme tiredness
- Lack of appetite
- Abdominal pain (stomach pain)
- Yellowing of the skin or whites of the eyes (jaundice).
Yet, not everyone infected with the hepatitis B virus will develop symptoms. With hepatitis B, a person can also develop a long-term liver infection (known as chronic hepatitis B).
How Is the Virus Spread?The hepatitis B virus is spread through infected bodily fluids. Among these bodily fluids are infected blood and blood products. Exposure to infected blood or blood products can occur through working in a laboratory or a dialysis unit, through infected needles used for tattoos or body piercing, or through sharing drug needles. In a few cases, people have been infected with hepatitis B by sharing objects that may have a tiny amount of blood on them, such as a toothbrush, razor, or tools used for manicures.
Hepatitis B is also spread through contact with other infected bodily fluids, such as semen, vaginal fluids, or saliva. A person cannot get the virus from a kiss or other normal everyday activities, such as hugging or shaking hands.
(Click Hepatitis B Transmission for more information about activities that put a person at high risk of developing the condition.)