Infection with the hepatitis B virus (HBV) may be without any symptoms, mild or severe. Among adults infected by HBV, 90 percent to 94 percent recover completely and have no long term effects. Six percent to 10 percent will become chronic carriers of HBV and will be at risk of developing cirrhosis or liver cancer. Over time, hepatitis B can destroy the liver (cirrhosis) and can cause liver cancer.
HBV is spread by direct contact with blood or other body fluids of infected people. (Delta hepatitis is spread the same ways as HBV; however, it is a defective hepatitis virus that can only be acquired in the presence of hepatitis B virus.)
Each year, an estimated 200,000 to 300,000 persons in the United States become infected with HBV. In Illinois, there were 591 cases of HBV reported in 1990; this declined to 315 reported cases in 1994.
Since the disease is not easily spread, persons with HBV do not pass the virus to others through casual contact, such as shaking hands or sharing a work space or bathroom facility. HBV is most commonly transmitted by sharing drug needles, by engaging in high-risk sexual behavior (especially anal sex), from a mother to her baby during childbirth and in the health-care setting.