"Hepatitis" simply means inflammation of the liver. The word sounds like one condition, but the three viruses behind hepatitis A, B and C behave very differently, spread in different ways and leave different traces in the blood. That is why a hepatitis A, B and C blood test is really a small collection of separate measurements, each answering its own question.
This guide walks through what the tests in the BPR catalogue measure, who usually considers them and how the sample is collected. It is general information: the right test for you depends on your history, and a health professional is the best person to help you choose.
Three viruses, three stories
Hepatitis A
Hepatitis A is usually picked up from contaminated food or water, or through close contact with someone who has it. In most people it is a short-lived illness that does not become a long-term infection, and a vaccine is available (Van Damme et al., 2023). Travellers to countries where hepatitis A is common often ask about their immunity before a trip.
Hepatitis B
Hepatitis B spreads through blood and other body fluids. According to the NHS, it often settles within a few months, but when the infection lasts longer than six months it is called chronic hepatitis B. Children in the UK are routinely vaccinated, and adults are usually only vaccinated if they are at higher risk, for example because of their job, travel or a liver or kidney condition (NHS, Hepatitis B). Chronic hepatitis B remains a major global health issue, and blood markers are central to how it is followed over time (Jeng et al., 2023).
Hepatitis C
Hepatitis C also spreads mainly through blood. The NHS notes that many people with hepatitis C have no symptoms at all, yet if it is not treated it can cause serious damage to the liver. The good news is that it can be treated with antiviral tablets, usually taken every day for 8 to 12 weeks (NHS, Hepatitis C; Martinello et al., 2023). Because symptoms are often absent, testing is the only way to know.
What the hepatitis A, B and C blood test measures
The Hepatitis A, B & C Profile from LML brings 12 markers together in one sample. According to LML, it looks for antibodies and antigens related to the three viruses and adds a liver function panel, because liver results can be affected by hepatitis infections. In practical terms it includes:
- Hepatitis A IgG/IgM antibodies: signs that the immune system has met hepatitis A, either through infection or vaccination.
- Hepatitis B surface antigen: a part of the hepatitis B virus itself.
- Hepatitis B core antibody (total): a marker of past or current contact with hepatitis B.
- Hepatitis C antibody: the immune response to hepatitis C.
- Liver function markers: albumin, total protein, globulin, bilirubin, ALT, AST, ALP and GGT.
This profile suits people who want a broad picture in a single request. Someone with a narrower question may prefer a single test.
The single tests, one by one
- Hepatitis A Immunity (IgG/IgM): LML explains that it assesses the immune response to hepatitis A and can show whether someone has been exposed to the virus before or has received the vaccine.
- Hepatitis A (IgM): IgM antibodies appear in a recent infection. LML describes this as the test used for acute hepatitis A, so it belongs with a clinician's assessment of current symptoms.
- Hepatitis B Profile: surface antigen, surface antibody and core antibody. LML lists screening of people at risk, monitoring of a known infection and checking vaccine response among its uses.
- Hepatitis B Immunity (Quantitative): measures the surface antibody (anti-HBs). It is the test people usually think of when they want to know whether their hepatitis B vaccination produced a response, for example before starting work in healthcare.
- Hepatitis C Antibodies: LML points out that a positive result shows past exposure and does not necessarily mean the virus is still present. Further testing is needed to answer that question.
Antibody or antigen: why the difference matters
An antigen is a piece of the virus. An antibody is the body's response to it. Finding an antigen suggests the virus is present; finding an antibody tells you the immune system has met the virus, or a vaccine, at some point. Reading these markers together is what gives them meaning, which is why results are best interpreted by a professional who knows your history (Jeng et al., 2023).
Timing matters too. The NHS notes that if a hepatitis C result is negative after a recent possible exposure, you may be advised to test again in six months (NHS, Hepatitis C).
