肝炎是一种很“沉默”的疾病,相当多的人感染病毒后是隐性感染,没有明显的异样,甚至病毒会在人体潜伏很久。然而一旦爆发,那就相当危险。因此,预防接种和定期检查都很有必要。中国超过半数乙肝病毒携带者是通过母婴垂直传染,或在4岁以前由亲属亲密接触而被感染。婴幼儿由急性乙肝转变为 Hepatitis is a very “silent ” disease, a considerable number of people infected with the virus is a latent infection, there is no obvious abnormalities, and even the virus will be latent in the human body for a long time. However, once it breaks out, it is quite dangerous. Therefore, both vaccination and regular screening are necessary. More than half of hepatitis B virus carriers in China are infected through vertical transmission from mother to child, or by intimate contact with their relatives before the age of 4 years. Infants and young children from acute hepatitis B into