Hepatitis B virus (HBV) is responsible for causing an acute as well as chronic infection of liver (also known as hepatitis B). It is transferred via semen, blood and other body fluid of an infected person to non-infected individuals and the initial diagnosis is Hepatitis B Surface Antigen test. The body fluid can be transferred through shared syringes or needles, sexual contact or by using other mutually shared injecting equipment or from a mom to her baby at birth. In some cases, hepatitis B is short term or acute illness but in other cases it may be chronic or long-term infection.
What Is Hepatitis B Surface Antigen (HBsAg)?
It is a protein which is present on the surface of surface of HBV that entice or stimulate the immune system to produce antibodies. This surface antigen can be found in elevated concentration within the serum when checked during chronic or acute HBV infection. The presence of hepatitis B surface antigen serves as an indication that the person has been exposed to the virus. Once infected, it takes about 30-150 days to develop symptoms that are suggestive of hepatitis B infection.
Hepatitis B Surface Antigen Test
This antigen can be detected in the blood of an infected person within 12 weeks after the initiation of the infection; serving as an earliest sign to look for in hepatitis B infection. If the antigen is detectable after the period of 6 months, then it may indicate the progression of short term or acute hepatitis B turns into long term or chronic hepatitis B. In other words the infected person may spread HBV to other throughout his life.
Hepatitis B Blood Test Panel
The hepatitis virus panel is a series of blood tests used to detect current or past infection by hepatitis B. Your doctor may order a hepatitis panel if you have symptoms of hepatitis. It can screen blood samples for more than one kind of hepatitis virus at the same time.
The blood panel for hepatitis B is dependent upon the following 3 tests:
- Hepatitis B surface antigen test: HbsAg is the earliest marker of HBV infection therefore it is detected before the occurrence of any other symptom. Presence of antigen for a period of greater than 6 months indicates chronic HBV infection.
- Hepatitis B surface antibody test: Antibody is detected usually 4 weeks after the detection of antigen. It indicates the end of the infectious stage i.e. the infected person is no longer contagious. This surface antibody prevents recurrence of HBV infection in the future. This test is done in order to estimate the vaccination need. If the test shows both antigen and the antibody, then the infected person may still be contagious.
- Hepatitis B surface core antibody test: Hepatitis B surface core antibody is an antibody, made 1 month after the initiation of HBV infection, against the core antigen of the Hepatitis B. It is usually detected in people who have chronic HBV infection or people with a history of infection in the past. It is usually present for the lifetime. Therefore, when blood is donated to blood banks; it is screened for hepatitis B.
When Do I Need to Do the Test?
You’ll be recommended to get your test done if:
- Your doctor suspects you have HBV infection.
- You have been diagnosed with Hepatitis B.
Symptoms begin to develop gradually. At times either there are no symptoms or they are too mild. Following symptoms may serve as a red flag:
- Dark colored urine
- Jaundice or pale coloration of skin
- Fever
- Nausea
- Anorexia
- Fatigue
- Muscle ache
If you have been in contact with the individuals carrying the virus, you’ll need a test regardless. Risk factors associated with hepatitis B include:
- Working in an environment where you have frequent exposure to blood or blood products.
- If you are habitual of using shared needles for IV drug administration
- Being born to an infected mother
- Men having sex with men
- Having a close contact with an infected person
- Having sex with an infected person
- An elastic band is wrapped around the arm to diminish the blood flow and to make needle insertion easier
- The site of insertion is cleaned with an alcohol swab
- Needle is inserted into the vein
- A tube is attached with the needle to collect the blood
- Once blood sample is taken, the elastic band is removed
- Cotton ball or gauze pad is placed on the site of insertion; pressure is applied followed by bandage.
How the Test Is Done?
- An elastic band is wrapped around the arm to diminish the blood flow and to make needle insertion easier
- The site of insertion is cleaned with an alcohol swab
- Needle is inserted into the vein
- A tube is attached with the needle to collect the blood
- Once blood sample is taken, the elastic band is removed
- Cotton ball or gauze pad is placed on the site of insertion; pressure is applied followed by bandage.
Are There Any Risks?
Following risks may be associated with blood sampling:
- Development of small bruise at the site of insertion. This may be minimized by applying pressure once the needle is removed.
- Inflammation of vein, also known as phlebitis, after the removal of needle; however, it’s quite rare. It can be taken care of by warm compress multiple times each day.
- Unstoppable bleeding in people with bleeding disorders. This can be treated by administering blood thinning medications like warfarin and aspirin.
What Are the Results?
Results of the test may be assessed as:
Hepatitis B virus tests:
- Hepatitis B surface antigen: Active infection. If the antigen is detected for greater than 6 months, then it indicates chronic hepatitis B.
- Hepatitis surface antibody: Indicates the end stage of active infection and may serve as a marker of previously provided vaccine.
- Hepatitis B e-antigen: Active infectious and contagious state of the HBV infection.
- HBV DNA: Detects HBV DNA and marks the current active infectious state.
- Hepatitis B core antibody: Indicates that the person has been infected but doesn’t differentiate between present or past infection.
- Hepatitis B core antibody IgM: It indicates occurrence of HBV infection in past 6 months and may mark the beginning of chronic stage.
- Hepatitis B e-antibody: It indicates less active HBV infection.