Causes
Hepatitis C is an inflammatory disease of the liver caused by the hepatitis C virus (HCV). The virus belongs to the group of flaviviruses and is an enveloped, single-stranded RNA virus. Based on its genetic information, this virus can be divided into 6 groups (so-called genotypes), which are further subdivided into a total of 30 supotypes.
The genotypes differ according to where they occur in greater numbers (1-3 are mainly found in Europe, 4 almost exclusively in Africa) and how they respond to the various therapeutic options for hepatitis C. The hepatitis C virus is transmitted parenterally (literally translated: past the intestine), i.e. via blood and other body fluids. Infections are therefore particularly frequent in certain risk groups: For example, medical personnel or nursing staff who deal with infected persons have the risk of coming into contact with the blood of sick persons through needlestick injuries and thus becoming infected. Drug addicts who use drugs such as heroin, which must be injected into the blood, and who share injecting equipment also run a high risk of infection.
Infection is also possible via other contaminated sharp objects such as piercing devices or tattoo needles. In the past, hepatitis C was also more frequently caused by infected blood preserves, but thanks to reliable testing procedures for donated blood, this is now virtually non-existent. The same applies to the transplantation of liver (parts).
The viral load in body fluids other than blood (e.g. sperm, vaginal secretion, breast milk or saliva) is so low that the risk of infection is almost zero, although it is possible in principle. This is why sexual transmission is not as frequent as is generally assumed (in contrast to hepatitis B!) and occurs almost only when special sexual practices are used where there is an increased risk of bleeding due to injuries to the mucous membrane, such as during anal intercourse.
Transmission from an infected mother to her child is also possible both during pregnancy and delivery, the rate here is about 4 percent. If the virus enters the bloodstream, it makes its way through the body and only attacks liver cells. The exact mechanism that actually leads to the inflammatory reaction of the liver has not yet been fully clarified, but it is assumed that under the influence of the virus, certain cytotoxic (i.e. cell death inducing) defence cells (lymphocytes) are formed, which eventually cause the death of more liver cells. This then causes the typical symptoms of hepatitis, which result from the limited functional capacity of the liver, and in later stages especially jaundice (icterus).
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