What is being analysed?

Blood tests analyse specific hepatitis B virus (HBV) antigens and antibodies. Serological markers are used to identify different phases of HBV infection and determine whether a patient has acute or chronic infection, immunity due to previous infection or vaccination, or susceptibility to infection.

What does the result mean?

Hepatitis B surface antigen (HBsAg): Detected at elevated levels in serum during acute or chronic HBV infection. Its presence indicates that the person is infectious, except when it might be transiently positive within 30 days after a hepatitis B vaccine (HepB) dose.

Hepatitis B surface antibody (anti-HBs): Generally indicates recovery and immunity to HBV. Also develops in people who have been successfully vaccinated against hepatitis B.

Total hepatitis B core antibody (anti-HBc): Appears at the onset of symptoms in acute hepatitis B. Indicates previous or current HBV infection within an undefined time frame. Individuals immunised with the hepatitis B vaccine do not develop anti-HBc.

IgM antibody to hepatitis B core antigen (IgM anti-HBc): Positivity indicates recent HBV infection (<6 months). Indicates acute infection.

Why is this analysis performed?

It is performed to detect or confirm HBV infection. It is very useful if there are symptoms of hepatitis B or risk factors such as travelling to areas with high HBV prevalence, exposure to contaminated food, close contact with infected individuals, sexual contact with an infected person, working in healthcare or daycare settings, or sharing intravenous needles.

When should the analysis be carried out?

When there is suspicion of HBV infection or in high-risk situations.

Is there a required sample?

A blood sample is needed. No special preparation is required.

What do normal values mean?

Negative HBsAg: Absence of HBV surface antigen. 

What do altered values indicate?

Active infection: If HBsAg and anti-HBc are positive, and anti-HBs is negative. Chronic infection: If HBsAg is negative and anti-HBc is positive, with or without anti-HBs. Vaccination immunity: If HBsAg is negative, anti-HBc is negative, and anti-HBs is positive.