Who should get tested for hepatitis B?
It is important to get tested for hepatitis B if any of these things are true.
- You have symptoms of a hepatitis B infection.
- You could have picked up the virus. For example you were born in a country where hepatitis B is more common.
- You are pregnant – you will be offered a test as part of your pregnancy care.
In some places in the UK people who go to A&E have a test for hepatitis B and other viruses. If you do not want the test, tell the doctor.
Immigration removal centres and prisons
People going into an immigration removal centre should have a hepatitis B test. People going into prison should also have a test. If your test shows you don’t have hepatitis B, you should be offered hepatitis B vaccination.
Blood donors
If you donate blood it will be tested for hepatitis B and other viruses. Some people find out they have hepatitis B this way.
Some medical treatments can make hepatitis B flare up and damage the liver. So your doctors will test for the virus before you have these treatments. They include:
– having an organ transplant
– taking medicines that weaken your immune system (immunosuppression)
– some types of chemotherapy
What do hepatitis B tests look for?
Tests for hepatitis B look for several different things. These include parts of the virus (antigens) and antibodies made by your immune system to fight it. Together the results can show whether you have a hepatitis B infection now or have had one in the past.
You can read more about how testing works on the Testing for viral hepatitis page .
Most of the time tests use a fresh sample of blood. Sometimes dried blood spot testing is used instead. For example, when a baby needs to have a hepatitis B test. The person taking the sample uses a medical needle to prick the skin. They collect a few drops of blood on filter paper and let it dry. The paper is sent to a lab which can test the dried blood.
Most of the tests are looking to see if something is there or not. If the test finds what it is looking for, then the result is positive or reactive. If the test doesn’t find the target then it is negative or non-reactive.
A hepatitis B test usually checks for hepatitis B surface antigen. If the test is positive or reactive, you have a hepatitis B infection. Depending on the results, the lab might do other tests.
One test by itself might not give your doctor all the information they need. Doctors use all your results to work out what is going on and what to do. If you aren’t sure what your results mean, ask your doctor to talk through them with you.
These are the main things tests look for and what the results might mean.
Hepatitis B surface antigen (HBsAg)
If this test is positive or reactive, it means you currently have the virus in your blood. This could be an acute or chronic infection. If you continue to test positive after 6 months, it is a chronic infection.
If your surface antigen test result becomes negative or non-reactive, it means you have cleared the infection. This is common in acute hepatitis B.
Antibody against the core antigen (anti-HBc or HBcAb)
If this test is positive or reactive it means you have had a hepatitis B infection at some point. It could be a past or current infection.
Alanine transaminase (ALT)
ALT is released when liver cells are damaged or die. If your ALT level is above normal, this might mean your liver is being damaged. What is thought to be a normal ALT level is different for different people. Your doctor or nurse can explain what your result means.
Hepatitis B DNA (viral load)
This measures how much virus is circulating in your blood. This is linked to how likely it is that the virus can be passed on through your blood or other fluids. It also affects the chances of you developing serious liver disease.
Read more about DNA levels in different phases of chronic hepatitis B .
Antibody against the surface antigen (anti-HBs or HBsAb)
If this test is positive or reactive it means you are immune to hepatitis B.
That could be because you have been vaccinated. In this case you will test negative or non-reactive for antibody to the core antigen (anti-HBc).
Or you might have had an infection in the past that has been cleared by your immune system.
Hepatitis B envelope antigen (HBeAg)
If this test is positive or reactive it means that the virus is making copies of itself. Having higher levels can mean there is more chance of the virus being passed on.
If this test is negative or non-reactive it does not rule out hepatitis B. The virus can stop making the envelope antigen. In this case, you will probably test positive or reactive for antibody to the envelope antigen (anti-HBe).
Antibody against the envelope antigen (anti-HBe or HBeAb)
If this test is positive or reactive it shows your immune system has reacted to the virus’ envelope antigen. This can be a sign that an acute infection is being cleared. In chronic hepatitis B, it can mean your immune system is keeping the virus under control.
As part of diagnosing hepatitis B your doctor will also check:
- Whether there are any other things that could harm your liver such as how much alcohol you drink
- Whether you have any other infections, including tests for hepatitis C, hepatitis D and HIV
What happens if I have chronic hepatitis B?
If you are diagnosed with chronic hepatitis B you will be referred to a specialist doctor based in a hospital. This could be a hepatologist (liver specialist), a gastroenterologist (specialist in the digestive system including the liver) or an infectious diseases doctor (specialist in caring for people with chronic infections).
This doctor will do more tests, including blood tests and scans . These tests are to check how healthy your liver is and how serious any damage is. You will have tests to check for serious liver damage and scarring (fibrosis). This is usually a scan called transient elastography. Your doctor might call it a FibroScan.
In rare cases your doctor might want to do a biopsy . This involves using a long, thin needle to take a tiny sample from your liver. You have a local anaesthetic to numb the area. Doctors look at the sample under a microscope to help make a diagnosis.
It is very important that you have a test for hepatitis D. Speak to your doctor if you haven’t been told your hepatitis D result.
There are different types of hepatitis B virus. But this is unlikely to make a difference to how you are treated. So you will not usually have tests to find out the kind of hepatitis B you have.
Your doctor will also use your test results to decide whether you need to have treatment at the moment.
What happens if I have acute hepatitis B?
If you are diagnosed with acute hepatitis B, you will not usually need any treatment. In most cases the virus is cleared up by your immune system.
Read more about acute hepatitis B.
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Published July 2023
Review due: July 2026