Key points about hepatitis B
- Hepatitis B is a viral infection of the liver caused by the hepatitis B virus (HBV).
- It is transmitted through blood and bodily fluids, particularly during sexual intercourse, invasive procedures, or mother-to-child transmission.
- The infection can progress to a chronic form that can lead to cirrhosis and liver cancer.
- There is no treatment that can permanently eradicate the virus, but effective treatments control viral replication.
- Vaccination against hepatitis B is safe, highly effective and is the main means of prevention.
What is hepatitis B?
Hepatitis B is a viral infectious disease caused by a DNA virus belonging to the family of HepadnaviridaeAfter infection, the virus infects hepatocytes and can cause acute liver inflammation. In immunocompetent adults, acute infection most often resolves spontaneously with the acquisition of lasting immunity. However, when infection occurs in more vulnerable populations, such as infants or young children, it frequently progresses to a chronic infectioncharacterized by the persistence of the virus in the body. Chronic hepatitis B can progress silently for many years before developing complications such as cirrhosis,Hepatic insufficiency or hepatocellular carcinoma.
Hepatitis B worldwide
Hepatitis B remains a major global public health problemAccording to the most recent estimates from the World Health Organization (WHO), approximately 296 million people worldwide were living with chronic hepatitis B, and near 1,1 million deaths were attributable each year to complications of the infection, primarily cirrhosis and liver cancer. Prevalence varies greatly between regions. The most affected areas are theSub-Saharan Africa and the region of Western Pacificwhere transmission frequently occurs at birth or in early childhood. Southeast Asia and parts of Eastern Europe and the Middle East are also affected. In countries with low endemicity, such as Western Europe, hepatitis B primarily affects certain at-risk populations, including migrants from highly endemic areas, people who inject drugs, and those exposed to sexual risks. Despite the availability of an effective vaccine for over 40 years, hepatitis B remains responsible for high mortality due to insufficient screening and unequal access to care and treatment.
What are the symptoms of hepatitis B?
Acute hepatitis B virus infection is often asymptomatic or mildly symptomatic. When symptomatic, it manifests as intense fatigue, a moderate fever, nausea, abdominal pain, dark urine and sometimes a jaundiceChronic hepatitis B is most often asymptomatic for many years. Symptoms appear late, at the stage of liver complications, with a decline in general health, signs of liver failure, or manifestations related to cirrhosis or liver cancer. In some people, particularly those with weakened immune systems, the progression can be more rapid and severe.
Diagnosis of hepatitis B
The diagnosis of hepatitis B is based on blood testsThis test allows for the detection of virological markers (HBs antigen, anti-HBs and anti-HBc antibodies) and the assessment of viral replication activity. Quantification of HBV DNA allows for the assessment of viral load and guides therapeutic management. Additional tests, such as liver function tests, imaging, or non-invasive assessment of liver fibrosis, are used to evaluate the severity of liver damage. Screening is particularly recommended for at-risk individuals and pregnant women to prevent mother-to-child transmission.
Treatment of hepatitis B
There is no treatment that can completely eliminate the hepatitis B virus. However, some effective antiviral treatments These treatments allow for sustained control of viral replication, slowing disease progression and reducing the risk of complications. Treatment is indicated for certain individuals with chronic hepatitis B, depending on viral activity, liver inflammation, and the degree of fibrosis. It primarily relies on long-term administration of nucleos(t)ide analogs under regular medical supervision. Management also includes monitoring for complications and regular screening for hepatocellular carcinoma in at-risk patients.
Prevention of hepatitis B
Prevention of hepatitis B relies primarily on the vaccinationwhich is highly effective and well-tolerated. Universal infant vaccination, recommended by the WHO, is the most effective strategy for sustainably reducing transmission and mortality from the disease. In France, hepatitis B vaccination has been mandatory for all infants since 2018, with catch-up vaccination recommended for children and adolescents up to the age of 15. It is also mandatory for healthcare professionals. Prevention of mother-to-child transmission relies on systematic screening for hepatitis B in pregnant women and the prompt administration of the vaccine, combined if necessary with immunoglobulins, to the newborn. Other preventive measures include ensuring safe care and transfusions, reducing the risks associated with drug use, promoting condom use, and screening exposed individuals. Globally, improving vaccination coverage, screening, and access to treatment is essential to achieving the goal of eliminating hepatitis B as a major public health problem.
FAQ
Hepatitis B is transmitted through contact with infected blood or body fluids, primarily during unprotected sex, unsafe invasive procedures, or mother-to-child transmission during pregnancy or childbirth.
Acute infection is often asymptomatic or only mildly symptomatic (fatigue, mild fever, nausea, abdominal pain). Chronic infection can remain silent for years before progressing to serious liver complications such as cirrhosis or liver cancer.
Diagnosis is based on blood tests that detect specific markers of the virus (HBs antigen, anti-HBs and anti-HBc antibodies) and viral load (viral DNA). Further examinations assess the severity of liver damage.
There is no treatment that completely eliminates the virus. However, effective antiviral treatments can control viral replication, slow the progression of the disease, and reduce the risk of complications.
Prevention relies primarily on vaccination, which is safe and effective. It is recommended from birth, with systematic screening of pregnant women and appropriate care to prevent mother-to-child transmission. Other measures include improving the safety of medical practices, reducing risks associated with sexual behavior and drug use, and screening exposed individuals.
