Hepatitis is a viral infection caused by the Hepatitis B virus (HBV). This virus is capable of causing life-long infection, liver cirrhosis (scarring), liver failure, liver cancer, and death.
HBV is mainly found in the blood of infected individuals. Saliva, semen, vaginal secretions and breast milk also contain the virus but in lower concentrations as compared to the blood. Feces, nasal secretions, sputum, sweat, tears, urine, and vomit have not been implicated in the spread of Hepatitis B. Unless they are visibly contaminated with blood, the risk of contracting hepatitis B from these fluids is practically nonexistent. Hepatitis B is not transmitted by casual contact, hugging, by sharing eating utensils, through food or water, etc.
Hepatitis B Surface Antigen (HBsAg): It can be detected in high levels in serum during acute or chronic hepatitis. The presence of HBsAg indicates that the person is infectious.
Hepatitis B Surface Antibody (anti-HBs): The body normally produces antibodies to HBsAg as a part of the normal immune response to infection. The presence of anti-HBs is generally interpreted as indicating recovery and immunity from HBV infection. Anti-HBs also develops into a person who has been successfully vaccinated against hepatitis B.
Hepatitis B e Antigen (HBeAg):This is found in the serum during acute and chronic hepatitis B. The presence of Hepatitis B envelope antigen (HBeAg) indicates that the virus is replicating and the infected individual has high levels of HBV.
Hepatitis B e Antibody (anti-HBe): This is produced by the immune system temporarily during acute HBV infection.
Hepatitis B core antibody (anti-HBc) This is an antibody to the hepatitis B core antigen. The core antigen is found on virus particles but disappears early in the course of infection. This antibody is produced during and after an acute HBV infection and is usually found in chronic HBV carriers as well as those who have cleared the virus, and usually persists for life.