What is hepatitis B?
Hepatitis B is one of the most common liver inflammations caused by viruses (viral hepatitis) worldwide. Most of those affected become infected with the hepatitis B pathogens during sexual intercourse. The infection is acute or chronic.
According to the World Health Organization (WHO), around 296 million people worldwide were chronically infected with the hepatitis B virus in 2019, including around 14 million in Europe. The disease is most common in sub-Saharan Africa and East Asia, but also in the southern regions of Eastern and Central Europe. Around 1.5 million people are newly infected with the hepatitis B virus every year, and 780,000 die worldwide each year from the disease and its consequences such as liver cirrhosis and liver cancer.
Obligation to report
Hepatitis B is notifiable. This means that the doctor treating you must report all suspected and confirmed cases to the responsible health authority. This also applies to deaths caused by hepatitis B. The office forwards the data to the Robert Koch Institute, where it is recorded statistically. However, there is no obligation to isolate infected persons.
What are the symptoms of hepatitis B?
Around a third of all infected adults show no symptoms. In a further third, symptoms such as tiredness, lack of appetite, nausea and muscle and joint pain occur, but no jaundice. Finally, in the last third, jaundice is also present (in addition to the other symptoms).
Incubation period of hepatitis B
Doctors refer to the time between infection and the appearance of the first symptoms as the incubation period. For hepatitis B it is 45 to 180 days. On average, it takes 60 to 120 days (i.e. two to four months) for the disease to break out.
Acute hepatitis B: symptoms
Acute hepatitis B begins with non-specific symptoms such as loss of appetite, aversion to certain foods, nausea and vomiting, muscle and joint pain and a slight fever.
After around three to ten days, jaundice (icterus) occurs in some cases: The skin, mucous membranes and the whites of the eyes (sclera) turn yellowish. This is often seen in young children and people with a weak immune system. In addition, the stool often becomes discolored, while the urine turns dark.
Chronic hepatitis B: symptoms
- Fatigue
- Joint and muscle pain
- Loss of appetite
- Weight loss
- Occasional feeling of pressure under the right ribcage
In around one percent of those affected, the chronic inflammation develops into liver cancer or a shrunken liver (liver cirrhosis). The risk of liver cancer in people with hepatitis is even around 100 times higher than in the rest of the population. The development of liver cirrhosis is favored by alcohol abuse and an additional hepatitis C infection.
Additional infection with hepatitis D
People with hepatitis B may also be infected with the hepatitis D virus. Such an infection is only possible in the presence of hepatitis B viruses, as the hepatitis D virus alone is unable to replicate in human cells.
If such a super-infection occurs, the liver disease is more severe than with hepatitis B infection alone. Furthermore, the additional infection with the virus type D increases the risk of liver cirrhosis even further. The number of chronic cases also increases significantly from around ten percent to over 90 percent. Liver cancer is also favored: With a combined infection with hepatitis B and D, the malignant tumor forms earlier than with a hepatitis B infection alone.
How is hepatitis B transmitted?
The disease is often passed on via infected blood. People who handle blood and needles or other sharp objects in everyday life are therefore particularly at risk of hepatitis B infection. These include
- Medical staff
- Dialysis patients
- Drug addicts, especially through the sharing and multiple use of syringes and other equipment
- People who receive canned blood or blood plasma (blood products are now strictly controlled before administration)
- People who get pierced ears, tattoos or piercings under unhygienic conditions
Hepatitis B can also be transmitted from mother to child during pregnancy, birth and breastfeeding. If a mother is known to be infected with hepatitis B, the child is therefore actively and passively vaccinated within 12 hours of birth. In addition, under certain circumstances, antiviral therapy is advisable for the expectant mother during pregnancy, for example if the viral load is high and the disease is active.
Examinations and diagnosis
Hepatitis B is usually diagnosed serologically using a blood sample. A laboratory test is carried out to determine whether there is any evidence of hepatitis B viruses:
- Virus antigens: These are specific components of the protein envelope of viruses (HBs-Ag, HBc-Ag and HBe-Ag). Like the viral DNA, they allow direct detection of the pathogen.
- Specific antibodies: In the case of a hepatitis B infection, the immune system forms specific antibodies against the pathogen (such as anti-HBc). Their presence is an indirect pathogen detection.
The presence or absence of antigens and antibodies allow the doctor to draw valuable conclusions:
A current hepatitis B infection is present if the genetic material of the virus, the viral antigen HBs-Ag and the antibody type anti-HBc can be detected in the blood of the person affected. However, the anti-HBs antibody type is missing in this case. There is a risk of infection for other people.
If hepatitis B has been cured, anti-HBc antibodies (and usually also anti-HBs) circulate in the blood. The viral antigen HBs-Ag, on the other hand, is not detectable.
If only anti-HBs antibodies are found in the blood, but no other antibodies or hepatitis B virus antigens, this indicates that the person concerned has effective protection against hepatitis B vaccination.
Further tests
If hepatitis B is suspected, other parameters are also determined in the affected person’s blood sample. Elevated liver values (such as GPT, GOT, gamma-GT) indicate liver damage.
The doctor uses an ultrasound examination to assess the structure and size of the liver. In the case of chronic hepatitis, he may also take a tissue sample from the liver (liver biopsy) to determine the extent of the tissue damage.
Treatment
In the case of an acute infection, no specific hepatitis B therapy is usually necessary – the disease almost always heals spontaneously on its own. If necessary, however, the doctor will treat the symptoms. Affected people with severe cases are a special case. In these cases, drug treatment may be advisable.
In any case, those affected should take it easy physically, even rest in bed if necessary, and eat a high-carbohydrate, low-fat diet. It is also very important to avoid alcohol – detoxifying it would put additional strain on the diseased liver. For the same reason, it is important not to take any medications that are harmful to the liver, such as painkillers and female sex hormones (the pill).
- Nucleoside and nucleotide analogs: These inhibit the replication of hepatitis viruses and are usually available as tablets.
- Interferon-α and pegylated interferon α (PEG interferon α): They also have an antiviral effect and also stimulate the immune system. They are administered by injection.
The aim of drug therapy is to reduce the amount of virus in the blood as much as possible. This reduces the risk of liver cirrhosis and liver cancer as a result of chronic hepatitis B. However, chronic hepatitis B cannot usually be cured with medication. If the chronic liver inflammation has led to severe liver cirrhosis, the last treatment option is a liver transplant.
In some people with chronic hepatitis B, the viruses multiply only slightly, the liver values are often normal and the liver is (still) only slightly damaged. In this case, treatment is often limited to regular check-ups.
Course and prognosis
In around nine out of ten adults with acute hepatitis B, the liver inflammation heals spontaneously and without consequences within a few weeks and leads to lifelong immunity. Only rarely, in up to one percent of those affected, does hepatitis B become very severe and serious, sometimes even fatal (fulminant course).
In children, hepatitis B almost always (around 90 percent) takes a chronic course.
Prevention
The most effective measure to prevent hepatitis in the first place is a hepatitis vaccination. The active hepatitis B vaccine stimulates the immune system to produce specific antibodies against the pathogen. It is available as a single vaccine or as part of combination vaccines (e.g. together with the hepatitis A vaccine). Find out here who should be vaccinated against hepatitis A, how many booster vaccinations are necessary and at what intervals, and who pays for the vaccinations.
You can read everything you need to know about vaccination against hepatitis B in the article Hepatitis vaccination.
Further protective measures
To prevent hepatitis B, you should also always use a condom during sexual intercourse. This is particularly important if your sexual partner changes frequently.
In addition, healthy people and people infected with hepatitis B should not share a toothbrush, nail scissors or razor.
