乙型肝炎是乙型肝炎病毒(HBV)感染而引起的疾病。HBV 是一种具有高度传染性的病毒,它对人类具有专一性感染力。根据 WHO 肝炎小组的调查资料,世界各地受 HBV 感染的人数约有一亿七千三百万,而其中,亚洲大平洋地区受感染的人数最多,约占四分之三,即占一亿三千一百万。近年来,国内外的许多流行病学调查资料进一步证明,HBV 感染是肝硬变的重要病因之一,而且它与肝癌的发生有非常密切的关系因此,HBV 不仅对人类肝炎的发病上,而且对肝硬化、肝癌的发生都具有严重的作用。 Hepatitis B is a disease caused by hepatitis B virus (HBV) infection. HBV is a highly contagious virus that has a specific infective effect on humans. According to WHO Hepatitis Group survey data, there are about 173 million people infected with HBV worldwide, of which, the largest number is infected in the Asian Pacific region, accounting for about three-quarters, or 113 million One million. In recent years, many epidemiological survey data at home and abroad further evidence that HBV infection is one of the important causes of cirrhosis, and it has a very close relationship with the occurrence of liver cancer Therefore, HBV is not only on the incidence of human hepatitis, and Liver cirrhosis, the occurrence of liver cancer have a serious effect.