Skip to contentSkip to navigation

Hepatitis B

Hepatitis B is an inflammation of the liver caused by a virus. It is transmitted through contact with the blood or other bodily fluids of an infected person. Manifestations of the disease are highly variable, ranging from very mild forms that last only a few weeks to chronic forms with complications that can lead to cirrhosis or liver cancer. Hepatitis B tests can diagnose the presence of an acute or chronic liver infection, identify “healthy” carriers of the virus, detect all individuals who are protected by vaccination or a prior resolved hepatitis B infection, and much more.

The first tests used to diagnose the disease look for the hepatitis B surface antigen (HBsAg, or Australia antigen) in addition to antibodies produced by the body against this antigen (anti-HBs). Depending on the clinical situation, these tests will be followed by a measurement of HBeAg and anti-HBe antigen levels, associated with the patient’s infectiousness, or by a measurement of antibodies directed against a virus core particle (anti-HBc). In more complex cases, the total quantity of virus in the body (HBV DNA) can be measured. Refer to the sections concerning each of these tests.

Term of the Week

Hot zone

A hot zone is a section of a facility (sometimes an entire facility or even a city district) where there is a high risk of contamination by patients with an infectious disease. All individuals entering a hot zone must respect appropriate protective measures. By analogy, “cold zone” and “warm zone” are used to refer to areas where there is no infected individual or only individuals suspected of having an infection.