What is hepatitis?

Read all you need to know about hepatitis.

Hepatitis is the inflammation of the liver and is usually the result of a viral infection or excess toxins [1].   

The liver is a vital organ that processes nutrients, filters the blood, and fights infections. Heavy alcohol use, toxins, some medications, and certain medical conditions can cause hepatitis. 

There are several  types of hepatitis,  But the three most common viral types are: 

  • Hepatitis A 
  • Hepatitis B 
  • Hepatitis C 

Hepatitis can be acute (where the infection lasts for six months or less) or chronic (where inflammation lasts longer than six months) 

Usually, acute hepatitis presents no noticeable symptoms, but if symptoms do develop, they can include the following: 

  • Yellowing of the eyes and skin (jaundice) 
  • Fatigue 
  • Flu-like symptoms 
  • Pale stools 
  • Dark urine 
  • Unexplained weight loss 
  • Joint and muscle pains 
  • Abdominal pain 
  • Loss of appetite 

What is hepatitis A? 

Hepatitis A is an acute, short-term disease caused by the hepatitis A virus (HAV). Hepatitis A is commonly transmitted through food or water contaminated with faeces from an already infected person.  Therefore, hepatitis A is more likely to be found in countries where sanitation is poor.  

Hepatitis A is an acute viral infection. Though sometimes severe, it usually passes within a few months. , There is no treatment for hepatitis A, other than relieving the symptoms, such as itching and nausea.  

There is a vaccination available against hepatitis A for people at a high risk of infection or travelling to a high-risk country 

How is hepatitis A diagnosed? 

When liver cells are damaged by infection or inflammation, they leak their contents  

Liver cells have two enzymes, aspartate transferase (AST) and alanine transferase (ALT) which are present in much higher concentrations in the liver than they are in the blood. 

So, when the liver is damaged, a rise in AST and ALT can be detected in the blood.  

Although an increase in both AST and ALT indicates the liver cells are damaged, this increase alone doesn’t explain the cause of the damage. 

To discover whether the hepatitis A virus is responsible for liver damage, a blood test looking for antibodies against the virus is required.  

What is hepatitis B? 

Hepatitis B is caused by the hepatitis B virus (HBV) and is transmitted through contact with infectious body fluids of an infected individual, such as blood, semen, or vaginal secretions.  

The virus can be spread by having unprotected sex with an infected partner. HBV can also be passed from someone who is pregnant and infected - to their baby. 

If an adult is infected with the hepatitis B virus, usually they can fight it off and recover within a couple of months (sometimes with the help from antiviral medication).  

However, if a child is infected, they usually develop a long-term infection (chronic hepatitis B) which can lead to scarring of the liver and liver cancer However, this is becoming rarer due to hepatitis B screening during antenatal visits. 

In the UK, vaccination against hepatitis B is recommended for people in high-risk groups, such as: 

  • Healthcare workers 
  • People who inject drugs 
  • Men who have sex with men  
  • Children born to mothers with hepatitis B 
  • People travelling to high-risk countries 

In 2017, the hepatitis B vaccine was added to the routine immunisation programme in the UK to allow all children to benefit from protection from the virus [1]

How is hepatitis B diagnosed? 

Due to hepatitis B (and C) being caused by a long-term (chronic) infection, a different type of blood testing is used to diagnose the virus. These blood tests usually look for proteins from the surface of the virus, while others detect the viruses’ DNA. 

The specific DNA the hepatitis B blood tests look for include: 

  • Hepatitis B surface antigen (HBsAg) - A positive result for the HBsAg antigen shows a person is infected with the hepatitis B virus and can spread the virus to others through their blood. Testing for the HBsAg antigen alone is not enough to determine if the infection is acute or chronic. 
  • Hepatitis B surface antibody (HBsAb) - A positive result for the HBsAb antibody shows a person is protected/immune against the hepatitis B virus and therefore unable to spread the virus to others. This protection may be the result of the hepatitis B vaccine or a successful recovery from a past hepatitis B infection. This test is not routinely included in blood bank screenings. 
  • Hepatitis B core antibody (HBcAb) - A positive result for the HBcAb antibody shows a past or current hepatitis B infection. Unlike a positive result for the HBsAb antibody, the hepatitis B core antibody does not provide protection against the hepatitis B virus. But without testing for both the HBsAg and anti-HBs, the positive HBaAb result cannot be fully understood. 

What is hepatitis C? 

Within the UK, hepatitis C (HCV) is the most common type of viral hepatitis and similarly to hepatitis B, is spread through blood-to-blood contact with an infected individual.  

It is thought that recreational drug use and the sharing of needles play a large part in the spread of the virus.  

Hepatitis C is usually a chronic infection as for the majority of those infected with HCV, the virus will remain in the body for several years.  

Although there is currently no HCV vaccine available, hepatitis C can be treated with antiviral drugs. 

Hepatitis C often doesn't have any noticeable symptoms until the liver is significantly damaged. Because of this, many  people who are infected are unaware they have the virus and may have only flu-like symptoms 

Because these symptoms may also indicate a range of other health issues, the only way to know for certain if you are infected with hepatitis C is to have a blood test. 

How is hepatitis C diagnosed? 

When a virus enters the body, the immune system works hard to produce antibodies to fight the infection. 

A positive result from a hepatitis C antibody test indicates whether an individual has ever been exposed to HCV.  

But this positive result does not necessarily mean there is a current infection as the immune system may have cleared the virus from the body.  

A second blood test called a Polymerase Chain Reaction (PCR) test is required after a positive result to confirm a current infection. 

Related tests 

Have a look at our full range of hepatitis tests. We also work with employers and organisations that are looking to offer occupational immunity testing for employees. Contact our team for more information about employee health checks. 


  1. https://www.nhs.uk/conditions/hepatitis/  


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