Symptoms | Progression | Effects

Hepatitis A is almost always asymptomatic in children, but usually causes symptoms in adults. Typical symptoms include lack of appetite, intolerance to fatty foods and alcohol, exhaustion, headache, nausea, or feeling of pressure below the right costal arch. In about one in three cases, pronounced symptoms develop, such as dark urine, pale stool, and icterus (“jaundice”: yellowing of the skin and the eyes), often also accompanied by itching. The symptoms usually subside after two to six weeks. A so-called fulminant course with life-threatening acute liver failure only occurs in rare cases where the liver has already been damaged, for example by chronic hepatitis B or C; this risk increases with age. The infection resolves completely and provides lifelong protection from reinfection.

Acute hepatitis B causes no symptoms in about one-third of the cases, only mild symptoms similar to those of flu or common cold in another one-third of the cases, and pronounced symptoms such as yellowing of the eyes and the skin, dark urine, and pale stool in the last one-third of the cases. The symptoms are similar to those of hepatitis A (lack of appetite, aversion to fatty foods and alcohol, exhaustion, headache, nausea, vomiting, and upper abdominal pain). In about 0.5 to 1% of the cases, acute hepatitis B takes a fulminant course and can lead to liver failure. This risk increases with age. In more than 90% of the cases in adults, the immune system is able to control the hepatitis B virus and prevent its replication, even though some viruses remain in the liver cells. The infection is considered to have resolved if viral components are no longer detectable in the blood and antibodies are detected instead. Once resolved, hepatitis B imparts lifelong immunity = protection from reinfection.

In about three-quarters of the cases, acute hepatitis C does not cause any prominent symptoms and therefore usually goes unnoticed. Only in one-quarter of the cases do mild symptoms similar to those of hepatitis B develop, such as icterus (yellowing of the eyes and the skin), dark urine, and pale stool. About three-quarters of all HCV infections become chronic, i.e. the virus continues to replicate longer than six months after infection. The other infections resolve within six months. Chronic hepatitis C may also resolve spontaneously at a later point. Hepatitis C that has resolved spontaneously or with medication does not provide protection from reinfection.

Hepatitis B becomes chronic in up to 10% of the cases in adults and can progress in highly different ways. For example, there are many virus carriers without symptoms and without detectable viral replication; in these cases, infectivity is very low. In more than half of the cases, chronic hepatitis B takes a mild course, causing changes in liver enzymes and only microscopic signs of liver inflammation. The aggressive form involves progressive impairment of liver function by fibrosis (liver cells are replaced by connective tissue cells without being able to take over their function); if the condition persists for a long time, it often culminates in liver cirrhosis (= scarring and shrinking of the liver) and permanent damage to the liver. This may cause liver cell cancer to develop, which may also occur without cirrhosis in rare cases of hepatitis B.

HCV infections become chronic in about three-quarters of the cases. Most of these infections remain asymptomatic over several years or decades or only cause mild symptoms (fatigue, upper abdominal pain, exhaustion as well as recurring temporary elevation of liver enzymes). In some cases, the infection takes an aggressive course causing fibrosis (see above) and in some of these cases liver cirrhosis with progressive loss of liver function after several years or decades. Patients with HCV-related cirrhosis have an increased risk of developing liver cancer.