请仔细看CDC这一段: 几乎所有6岁以上儿童或成人感染乙肝病毒能完全康复而不发展为慢性感染

https://www.cdc.gov/hepatitis/hbv/index.htm?

"Not all people newly infected with HBV have symptoms, but for those that do, symptoms can include fatigue, poor appetite, stomach pain, nausea, and jaundice. For many people, hepatitis B is a short-term illness. For others, it can become a long-term, chronic infection that can lead to serious, even life-threatening health issues like liver disease or liver cancer. Age plays a role in whether hepatitis B will become chronic. The younger a person is when infected with the hepatitis B virus, the greater the chance of developing chronic infection. About 9 in 10 infants who become infected go on to develop life-long, chronic infection. The risk goes down as a child gets older. About one in three children who get infected before age 6 will develop chronic hepatitis B. By contrast, almost all children 6 years and older and adults infected with the hepatitis B virus recover completely and do not develop chronic infection."