At a glance

Also known as

HBV; Hep B; Anti-HBs (Hepatitis B antibodies); HBsAg (Hepatitis B surface antigen); HBeAg (Hepatitis B e antigen); Anti-HBc ( Hepatitis B core antibody)

Why get tested?

To diagnose and follow the course of an infection with hepatitis B or to determine if the vaccine against hepatitis B has produced the desired level of immunity

When to get tested?

If you have symptoms of a hepatitis B infection or are likely to have been exposed to the virus. Also to check if you are immune, or to monitor the disease progression.

Sample required?

A blood sample drawn from a vein in your arm

Test preparation needed?

None

What is being tested?

Hepatitis B is an infection of the liver caused by the hepatitis B virus (HBV). Hepatitis B blood tests detect viral proteins (antigens), the antibodies that are produced in response to an infection, or detect or evaluate the genetic material (DNA) of the virus. The pattern of tests results can identify a person who has a current active infection, was exposed to HBV in the past, or has immunity as a result of vaccination.

Hepatitis is a condition characterised by inflammation and, sometimes, enlargement of the liver. It has various causes, one of which is infection by a virus. HBV is one of five "hepatitis viruses" identified so far that are known to mainly infect the liver. The other four are hepatitis A, hepatitis C, hepatitis D and hepatitis E.

HBV is spread through contact with blood or other body fluids from an infected person. Exposure can occur, for example, through sharing of needles for IV drug use or through unprotected sex. People who live or travel to areas of the world where hepatitis B is prevalent area at a greater risk. Mothers who are infected can pass the infection to their babies, usually during or after birth. The virus is not spread through casual contact such as holding hands, coughing or sneezing. However, the virus can survive outside the body for up to seven days, including in dried blood, and can be passed by sharing items such as razors or toothbrushes with an infected person.

The course of HBV infections can vary from a mild form that lasts only a few weeks to a more serious chronic form lasting years. Sometimes chronic HBV leads to serious complications such as cirrhosis or liver cancer. Some of the various stages or forms of hepatitis B include:
 

  • Acute infection- presence of typical signs and symptoms with a positive HBV test
  • Chronic infection- persistent infection with the virus detected by laboratory tests accompanied by inflammation of the liver.
  • Carrier state- persistent infection (determined by HBV tests) but no liver inflammation (a carrier is someone who may appear to be in good health but harbours the virus and can potentially infect others)
  • Resolved or inactive infection- no longer has any evidence of infection; viral antigen and DNA tests are negative and no signs or symptoms of liver inflammation (although, in many cases, the virus is present in an inactive state in the liver and can potentially reactivate).
  • Reactivation- return of HBV infection (detected by HBV tests) with liver damage in a person who was a carrier or who had a resolved, inactive infection. This most commonly occurs in persons treated with chemotherapy for cancer or with drugs that suppress the immune system used to treat autoimmune diseases or following an organ transplant. It also can occur during treatment for hepatitis C (HCV) in people who also had been exposed to HBV in the past.
The vast majority of those with chronic infections will have no symptoms. For acute infections, the symptoms (when present) are very similar to those other types of acute hepatitis, although no symptoms occur in over half of those with acute HBV infection. Symptoms include fever, fatigue, nausea, vomiting and jaundice. With acute hepatitis, the liver is damaged and is not able to function normally. It may not process toxins or waste products such as bilirubin for their removal from the body. During the course of disease, bilirubin and liver enzyme levels in the blood may increase. While tests such as bilirubin or liver panel can tell a healthcare practitioner that someone has hepatitis, they will not inducate what is causing it. Tests that detect infection with  hepatitis virus may help determine the cause.

 
How is the sample collected for testing?

A blood sample is drawn by needle from a vein in your arm.

Is any test preparation needed to ensure the quality of the sample?

No test preparation is needed.

The Test

How is it used?

There are several tests used to detect the presence of hepatitis B antibodies. Antibodies are produced by the body in response to antigens (foreign proteins).

The hepatitis B surface antibody (anti-HBs) indicates previous exposure to HBV, but the virus is no longer present and the person cannot pass on the virus to others. The antibody also protects the body from future HBV infection. In addition to exposure to HBV, these antibodies can also be found after successful vaccination. This test is done following the completion of vaccination against the disease or following an active infection.

The following table summarises the set of tests typically used for initial testing:

Test Description Use and Comments
Hepatitis B surface antigen (HBsAG) Detects protein that is present on the surface of the virus To screen for, detect, and help diagnose acute and chronic HBV infections; earliest routine indicator of acute hepatitis B and frequently identifies infected people before symptoms appear; undetectable in the blood during the recovery period; it is the primary way of identifying those with chronic infections, including "HBV carrier" state.
Hepatitis B surface antibody (anti-HBs) Detects antibody produced in response to HBV surface antigen Used to detect previous exposure to HBV; it can also develop from successful vaccination so it is used to determine the need for vaccination (if anti-HBs is absent) or to determine if a person has recovered from an infection and is immune (cannot get the infection again).
Total anti-hepatitis B core (anti-HBc, IgM and IgG) Detects both IgM and IgG antibodies to hepatitis B core antigen Can be used to help detect acute and chronic HBV infections; the IgM antibody is the first antibody produced after infection with HBV; IgG antibody is produced in response to the core antigen later in the course of the infection and usually persists for life.
Anti-hepatitis B core (anti-HBc, IgM) Detects only the IgM antibody to the hepatitis B core antigen Used to detect acute infections; may be included in initial testing, e.g., when done as part of an acute viral hepatitis panelTest
Description
Use and Comments

Hepatitis B surface antigen (HBsAG)
Detects protein that is present on the surface of the virus
To screen for, detect, and help diagnose acute and chronic HBV infections; earliest routine indicator of acute hepatitis B and frequently identifies infected people before symptoms appear; undetectable in the blood during the recovery period; it is the primary way of identifying those with chronic infections, including "HBV carrier" state.

Hepatitis B surface antibody (anti-HBs)
Detects antibody produced in response to HBV surface antigen
Used to detect previous exposure to HBV; it can also develop from successful vaccination so it is used to determine the need for vaccination (if anti-HBs is absent) or to determine if a person has recovered from an infection and is immune (cannot get the infection again).

Total anti-hepatitis B core (anti-HBc, IgM and IgG)
Detects both IgM and IgG antibodies to hepatitis B core antigen
Can be used to help detect acute and chronic HBV infections; the IgM antibody is the first antibody produced after infection with HBV; IgG antibody is produced in response to the core antigen later in the course of the infection and usually persists for life.

Anti-hepatitis B core (anti-HBc, IgM)
Detects only the IgM antibody to the hepatitis B core antigen
Used to detect acute infections; may be included in initial testing, e.g., when done as part of an acute viral hepatitis panel

The following table summarises tests that may be used as follow-up after initial tests detect an HBV infection:
 
Hepatitis B e-antigen (HBeAG) Detects protein produced and released into the blood Often used as a marker of ability to spread the virus to other people (infectivity); it may also be used to monitor the effectiveness of treatment. However, there are some types (strains) of HBV that do not make e-antigen; these are especially common in the Middle East and Asia. In areas where these strains of HBV are common, testing for HBeAg is not very useful to determine whether the virus can be spread to others.
Anti-hepatitis B e antibody (Anti-HBe) Detects antibody produced by the body in response to the hepatitis B "e" antigen Used to monitor acute infections in those who have recovered from acute hepatitis B infection; anti-HBe will be present along with anti-HBc and anti-HBs.
Hepatitis B viral DNA Detects hepatitis B viral genetic material in the blood A positive test indicates that the virus is multiplying in a person's body and that person is contagious. The test is often used to monitor the effectiveness of antiviral therapy in people with chronic HBV infections.
Hepatitis B virus resistance mutations Detects mutations in the particular virus causing a person's infection that allows the virus to be resistant to treatments (reverse transcriptase inhibitors) Helps to select appropriate treatment, especially in people who have been treated previously or in those who are not responding to treatment

While the tests described above are specific for HBV, other liver tests such as aspartate aminotransferase (AST), alanine aminotransferase (ALT), and gamma-glutamyl transferase (GGT) may be used to monitor the progress of the disease. In some cases, a liver biopsy may be performed to evaluate how much damage has occurred to the liver.
 

When is it requested?

These tests are used to determine whether the vaccine has produced the desired level of immunity as well as to diagnose and follow the course of an infection.

In a patient with acute hepatitis, IgM anti-HBc and HBsAg are usually requested together to detect recent infection by HBV. In persons with chronic hepatitis, or with elevated ALT or AST, HBsAg and anti-HBc are usually done to see if the liver damage is due to HBV. If so, HBsAg and HBeAg are usually measured on a regular basis (every 6 months to a year), since in some people HBeAg (and, less commonly, HBsAg) will go away on its own.

In those who are being treated for chronic HBV, HBeAg and HBV DNA can be used to determine whether the treatment is successful. If a person is given the HBV vaccine, anti-HBs is used to see if it successful; if levels of the antibody are over 10 mIU/mL, the person is probably protected for life from infection by HBV.

All donated blood is tested for the presence of the HBsAg and HBV DNA before being distributed.

What does the test result mean?

Hep B surface antigen (HBsAg) Hep B surface antibody (Anti-HBs) Hep B core antibody Total (Anti-HBc IgG+IgM) Hep B core antibody (Anti-HBc IgM) Hep B e antigen (HBeAg)* Hep B e antibody (Anti-HBe) HBV DNA Possible Interpretation / Stage of Infection
Negative Negative Negative Negative Not performed Not performed Not performed No active or prior infection; not immune — may be good candidate for vaccine; possibly in the incubation stage
Negative Positive Negative Not performed Not performed Not performed Not performed Immunity due to vaccination
Negative Positive Positive Not performed Not performed Not performed Not performed Infection resolved; virus can reactivate if immune system suppressed
Positive Negative Positive or Negative Positive Positive or negative Negative Detected Acute infection, usually with symptoms; contagious; could also be flare of chronic infection
Negative Negative Positive Positive Negative* Positive None detected Acute infection is resolving (convalescent)
Positive Negative Positive Negative Positive* or Negative Negative or Positive Detected Usually indicates an active chronic infection (liver damage likely)
Positive Negative Positive Negative Negative Positive None detected or detected at very low level Chronic infection but low risk of liver damage — carrier state
*Note: There are some types (strains) of HBV that do not make e-antigen. In areas where these strains of HBV are common (in the Middle East and Asia), testing for HBeAg is not very useful. In these cases, a negative HBeAg result does not necessarily mean that the person is not infectious; it may be that the person is infected with a strain that does not make the e-antigen.

Monitoring treatment of chronic infection: If the results from initial follow-up testing indicte that a person has chronic hepatitis B, then the individual may be treated with medication and the effectiveness of that treatment may be monitored using the tests for HBe and HBs antigen and antibody and HBV DNA.
  • If HBsAg becomes negative and anti-HBs becomes positive during treatment, this usually indicates that treatment is effective and that treatment can be discontinued after an additional 6-12 months.
  • If HBeAg becomes negative and anti-HBe becomes positive during treatment, this usually indicates that is effective and that treatment  may be discontinued after an additional 6-12 months, although the virus may reappear later, so continued monitoring is needed.
  • HBV DNA measures the amount of virus present in the blood. A high result usually means that the virus is actively replicating and that treatment is not effective. A low result or one that is reported as below a lower limit ( none detected) means the virus is not present or is present in such a low numbers that it cannot be detected. This is usually indicates that the therapy is effective in controlling replication of the virus, however, the virus may reappear if the treatment is stopped. 

Is there anything else I should know?

Even if you don't have symptoms, an HBV infection can damaage your liver and you can spread the infection to others. For this reason, it is important to get tested if you think you have been exposed to HBV.

Blood banks screen all donated blood for the hepatitis B virus (HBV DNA), hepatitis B surface antigen (HBsAg), and hepatitis B core antibody ( anti-HBc). Donors are notified of any confirmed positive reactions. People who receive a notice regarding possible infection with hepatitis B after donating should visit their healthcare provider for further testing. The healthcare practitioner wil order additional tests to make a proper diagnosis and determine if treatment is necessary.

If exposed to HBV and you haven't been vaccinated, an infection can be avoided by getting a shot of hepatitis B immune globulin (HBIG) within 24 hours and typically you will also be given the first dose of the hepatitis B vaccine.

A test is available to determine the specific type (strain) of hepatitis B virus that is causing a person's infection. This is called HBV genotyping. However, this testing is currently mainly used in research settings and not for clinical purposes.
 

Common Questions

If it is possible that I have an HBV infection, will I need to have all of these tests done?

No. Your doctor will determine which test(s) will be appropriate for your symptoms and history.

Should I have the HBV vaccine?

Yes. Unless there is something in your medical history to the contrary, it is prudent to have the series of vaccinations. Pregnant women are routinely tested for infection and, if positive, immunoglobulin and vaccination of the newborn baby is offered. Periodic measurement of anti-HBs in persons who have developed immunity to HBV is not needed; even if their antibody level falls below 10 mIU/mL, they still appear to be protected if exposed to the virus.

Can I test myself for immunity?

No. This test is performed by trained laboratory staff.

Last Review Date: December 30, 2018