4. 症状是什么？
乙型肝炎也常常被称为“隐匿疾病”，因为许多感染者从未意识到自己已经染上了病。假若有症状的话，也要到数周或数月后才能够出现。可是，其中大多数感染者根本就不发病或仅有暂时流感样症状，诸如疲劳、食欲不振、浑身关节与肌肉疼痛和低烧等症状。只有少数病人发展成更严重的“急性肝炎”。这种病人另外的症状之一是可能出现“黄疸”，也就是皮肤和眼睛发黄。无论如何，大多数病人数周后会恢复健康，而且决不会再有任何肝炎症状。
某些“急性肝炎”病人随后发展成“慢性肝炎”。同样的地，他们可以根本无症状，或可能有一系列症状出现，少数人的症状非常严重并且衰弱不堪。有的症状或并发症甚至可能威胁到生命，诸如肝硬化（皱缩和疤痕形成）或肝癌。

5. 如何诊断？
因为许多感染者仅有轻微和暂时的症状或根本无症状，仅有的可靠诊断方法是血液检测。

Hepatitis B II (HBV)

4. What are the symptoms?
Hepatitis B is often also called a “silent disease”, because many infected people never realize that they have it. If there are symptoms, they do not develop until a few weeks or months after the infection. Most of the infected, however, do not get sick at all or have only temporary flu-like symptoms like fatigue, a loss of appetite, pain in various joints and muscles, a light fever etc. Only in a minority of patients is this “acute hepatitis” more serious. Among other problems, they may develop “jaundice”, i.e. a yellow coloration of the eyes and the skin. Anyway, most patients recover after a few weeks and never have any hepatitis problems again.
In some cases “acute hepatitis” is followed by “chronic hepatitis”. Again, there may be no symptoms at all, or there may be a variety of problems, some of them very serious and debilitating. They may even be life-threatening like cirrhosis (shrinking and scarring) of the liver or liver cancer.

5. How is it diagnosed?
Since many people infected with HBV have only slight, temporary symptoms or no symptoms at all, the only certain way to diagnose the disease is a blood test.