1. Hepatitis B Surface Antigen (HBsAg) Test
- Purpose: To determine whether a person is currently infected with HBV.
- What It Means: If HBsAg is positive, the person is actively carrying HBV and is contagious. This test is usually used to detect acute or chronic Hepatitis B infection.
2. Hepatitis B Surface Antibody (anti-HBs) Test
- Purpose: To determine whether a person has developed immunity to Hepatitis B.
- What It Means: If anti-HBs is positive, the person has either been vaccinated against Hepatitis B and is immune, or has had a previous infection and recovered.
3. Hepatitis B Core Antibody (anti-HBc) Test
- Purpose: To determine whether a person has been infected with HBV in the past.
- What It Means: If anti-HBc is positive, the person is either currently infected or may have been infected in the past. This test alone is not sufficient to determine whether the infection is acute or chronic, so it is usually evaluated in conjunction with other tests.
- IgM anti-HBc: Indicates an acute or recent infection.
- IgG anti-HBc: Indicates a recent or chronic infection.
4. Hepatitis B e Antigen (HBeAg) and e Antibody (anti-HBe) Test
- Purpose: To determine the degree of contagiousness of HBV and the viral load of a person What Does It Mean:
- HBeAg positive: Indicates high levels of viral replication and infectiousness.
- Anti-HBe positive: Indicates decreased viral replication and low infectiousness.
5. Hepatitis B DNA (HBV DNA) Test
- Purpose: To measure the amount of HBV in a person's blood (viral load test).
- What It Means: The HBV DNA test is used to determine how active the virus is in the body and how it is responding to treatment. High HBV DNA levels are an indicator of active viral replication and a high risk of infection.
Hepatitis B Tests During Pregnancy
Hepatitis B tests performed during pregnancy are important to determine whether the expectant mother is an HBV carrier. These tests include:
- HBsAg Test: The HBsAg test, performed in early pregnancy (first trimester), is performed to determine whether the mother is an HBV carrier.
- Anti-HBs and Anti-HBc Tests: If HBsAg is positive, additional tests may be performed to determine whether the infection is acute or chronic.
- HBV DNA Test: For HBsAg positive mothers, it can be done to determine viral load and assess the risk of transmission to the baby during birth.
Interpretation of Test Results
Interpretation of test results should be done by a health professional. The table below summarizes the possible results of the basic tests and what they mean:
|
Test
|
Positive Result
|
Negative Result
|
|
HBsAg
|
Active HBV infection
|
No HBV infection
|
|
Anti-HBs
|
Immunity (after vaccination or recovery)
|
No immunity
|
|
Anti-HBc
|
Past or current HBV infection
|
No HBV infection
|
|
HBeAg
|
Highly infectious
|
Low or not infectious
|
|
Anti-HBe
|
Decreased infectiousness
|
Infectiousness status cannot be determined
|
|
HBV DNA
|
High viral load
|
Low or undetectable viral load
|
This tests are necessary to detect Hepatitis B infection, determine the stage of the infection, and take appropriate treatment and precautions. These tests are especially important during pregnancy to protect the health of the mother and the baby.