Hepatitis B, which is sometimes referred to as HBV, is a viral liver infection that is transmitted through contact with an infected person's blood or other bodily fluids, according to the World Health Organization. Hepatitis B attacks the liver and can cause a potentially life-threatening liver infection. The WHO says that more than 780,000 people die each year from complications or illnesses caused by hepatitis B.
Mayo Clinic notes a range of different ways that HBV is transmitted. Sexual contact with an infected person's blood, semen, vaginal secretions or saliva is one common form of transmission. Syringes and needles shared among intravenous drug users can be a source of transmitting HBV. In healthcare settings, workers are at risk for coming into contact with the virus via accidental needle sticks. Newborn babies can get HBV from their mothers during childbirth.
Mayo Clinic reports that there are two types of hepatitis B: acute and chronic. Acute infections last for less than six months, and most people completely recover. Chronic infections last for six months or longer, and many chronic infections last for the infected person's lifetime. Chronic hepatitis B infection can also lead to more ominous conditions including liver cancer and cirrhosis of the liver.
A vaccine that guards against hepatitis B has been available since 1982. WHO notes that this vaccine is approximately 95 percent effective against hepatitis B.