Hepatitis B is an infection of the liver caused by a virus that's spread through blood and body fluids.

It often doesn't cause any obvious symptoms in adults and typically passes in a few months without treatment. But in children, it often persists for years and may eventually cause serious liver damage.

Hepatitis B is less common in the UK than other parts of the world, but certain groups are at an increased risk. This includes people originally from high-risk countries, people who inject drugs and people who have unprotected sex with multiple sexual partners.

A hepatitis B vaccine is available for people at high risk of the condition.

This page covers:

Symptoms of hepatitis B

When to get medical advice

Treatments for hepatitis B

How hepatitis B is spread

Preventing hepatitis B

Outlook for hepatitis B

Symptoms of hepatitis B

Many people with hepatitis B won't experience any symptoms and may fight off the virus without realising they had it.

If symptoms do develop, they tend to occur two or three months after exposure to the hepatitis B virus.

Symptoms of hepatitis B include:

• flu-like symptoms, including tiredness, a fever, and general aches and pains
• loss of appetite
• feeling and being sick
• diarrhoea
• tummy (abdominal) pain
• yellowing of the skin and eyes (jaundice)

These symptoms will usually pass within one to three months (acute hepatitis B), although occasionally the infection can last for six months or more (chronic hepatitis B).

Read more about the symptoms of hepatitis B.

When to get medical advice

Hepatitis B can be serious, so you should get medical advice if:

• you think you may have been exposed to the hepatitis B virus – emergency treatment can help prevent infection if given within a few days of exposure
• you have symptoms associated with hepatitis B
• you're at a high risk of hepatitis B – high-risk groups include people born in a country where the infection is common, babies born to mothers infected with hepatitis B, and people who have ever injected drugs

You can go to your local GP surgery, drug service, genitourinary medicine (GUM) clinic or sexual health clinic for help and advice.

A blood test can be carried out to check if you have hepatitis B or have had it in the past. The hepatitis B vaccine may also be recommended to reduce your risk of infection.

Treatments for hepatitis B

Treatment for hepatitis B depends on how long you've been infected for:

• If you've been exposed to the virus in the past few days, emergency treatment can help stop you becoming infected.
• If you've only had the infection for a few weeks or months (acute hepatitis B), you may only need treatment to relieve your symptoms while your body fights off the infection.
• If you've had the infection for more than six months (chronic hepatitis B), you may be offered treatment with medicines that can keep the virus under control and reduce the risk of liver damage.

Chronic hepatitis B often requires long-term or lifelong treatment and regular monitoring to check for any further liver problems.

Read more about treating hepatitis B.

How hepatitis B is spread

The hepatitis B virus is found in the blood and bodily fluids, such as semen and vaginal fluids, of an infected person.

It can be spread:

• from a mother to her newborn baby, particularly in countries where the infection is common – read more about hepatitis B in pregnancy
• within families (child to child) in countries where the infection is common
• by injecting drugs and sharing needles and other drug equipment, such as spoons and filters
• by having sex with an infected person without using a condom
• by having a tattoo, body piercing, or medical or dental treatment in an unhygienic environment with unsterilised equipment
• by sharing toothbrushes or razors contaminated with infected blood

Hepatitis B is not spread by kissing, holding hands, hugging, coughing, sneezing, or sharing crockery and utensils.

Read more about the causes of hepatitis B.

Preventing hepatitis B

A vaccine that offers protection against hepatitis B is available for all babies born in the UK on or after August 1 2017. It is also available for people at high risk of the infection or complications from it.

This includes:

• babies born to hepatitis B-infected mothers
• close family and sexual partners of someone with hepatitis B
• people travelling to a part of the world where hepatitis B is widespread, such as sub-Saharan Africa, east and southeast Asia, and the Pacific Islands
• families adopting or fostering children from high-risk countries 
• people who inject drugs or have a sexual partner who injects drugs
• people who change their sexual partner frequently
• men who have sex with men
• male and female sex workers
• people who work somewhere that places them at risk of contact with blood or body fluids, such as nurses, prison staff, doctors, dentists and laboratory staff
• people with chronic liver disease
• people with chronic kidney disease
• prisoners 
• people receiving regular blood or blood products, and their carers 

The hepatitis B vaccine is given to infants as part of the routine child vaccination schedule and to those who are at high risk of developing the infection.

You do not need to pay for the vaccine if your child is eligible to receive it as part of the routine child vaccination schedule or if born to a hepatitis B-infected mother. Others may have to pay for it.

Read more about hepatitis B vaccination.

Outlook for hepatitis B

The vast majority of people infected with hepatitis B in adulthood are able to fight off the virus and fully recover within one to three months. Most will then be immune to the infection for life.

Babies and children with hepatitis B are more likely to develop a chronic infection. Chronic hepatitis B affects around:

• 90% of babies with hepatitis B
• 20% of older children with hepatitis B
• 5% of adults with hepatitis B

Although treatment can help, there's a risk that people with chronic hepatitis B could eventually develop life-threatening problems such as scarring of the liver (cirrhosis) or liver cancer.

Read more about complications of hepatitis B.

Only some people with hepatitis B experience symptoms, which usually develop two or three months after exposure to the hepatitis B virus.

Many people infected in adulthood won't experience any symptoms and will fight off the infection without realising they had it.

However, they'll still be able to pass the virus on to others while they're infected.

Read more about how hepatitis B is spread.

Main symptoms of hepatitis B

Symptoms of hepatitis B can include:

• tiredness
• general aches and pains
• a high temperature (fever) of 38C (100.4F) or above 
• a general sense of feeling unwell
• loss of appetite
• feeling and being sick
• diarrhoea
• tummy (abdominal) pain
• yellowing of the skin and eyes (jaundice)
• dark urine and pale, grey-coloured poo

Many of these symptoms can be mistaken for more common illnesses, such as flu or gastroenteritis.

How long do symptoms of hepatitis B last?

Hepatitis B in adults will usually pass within one to three months. This is known as acute hepatitis B and rarely causes any serious problems.

Occasionally, the infection can last for six months or more. This is known as chronic hepatitis B.

Chronic hepatitis B mainly affects babies and young children who get hepatitis B. It's much less common in people who become infected later in childhood or when they're an adult.

The symptoms of chronic hepatitis B are the same as those mentioned above, but they tend to be quite mild and may come and go. Some people may not have any noticeable symptoms.

However, without treatment, people with chronic hepatitis B can develop problems such as scarring of the liver (cirrhosis).

Read more about treatments for hepatitis B and complications of hepatitis B.

Hepatitis B is an infection caused by the hepatitis B virus. The virus is found in the blood and bodily fluids of an infected person.

Many people with hepatitis B have few symptoms and may not know they're infected. They may spread the infection without realising it.

Hepatitis B is most often caught in parts of the world where the infection is more common, although certain groups of people are at risk of picking up the infection in the UK.

How hepatitis B is spread

Hepatitis B can be spread by:

• a mother to their newborn baby, particularly in countries where the infection is common – all pregnant women in the UK are offered screening for hepatitis B; babies of infected mothers are vaccinated immediately after birth to help prevent infection
• injecting drugs and sharing needles and other drug equipment, such as spoons and filters
• having sex with an infected person without using a condom
• having a tattoo, body piercing, or medical or dental treatment in an unhygienic environment with unsterilised equipment
• having a blood transfusion in a country where blood isn't tested for hepatitis B – all blood donations in the UK are now tested for the infection
• sharing toothbrushes or razors contaminated with infected blood
• the skin being accidentally punctured by a used needle (needle stick injury) – this is mainly a risk for healthcare workers
• the blood of someone with hepatitis B getting into an open wound, cut, or scratch – in rare cases, being bitten by someone with hepatitis B can also spread the infection

Hepatitis B isn't spread by kissing, holding hands, hugging, coughing, sneezing, or sharing crockery and utensils.

Who's most at risk of hepatitis B?

People at highest risk of hepatitis B include:

• people born or brought up in a country where the infection is common
• babies born to mothers infected with hepatitis B
• people who have ever injected drugs
• anyone who has had unprotected sex, including anal or oral sex – particularly people who've had multiple sexual partners, people who've had sex with someone in or from a high-risk area, men who have sex with men, and commercial sex workers
• close contacts, such as family members, of someone with long-term (chronic) hepatitis B infection

The risk of getting hepatitis B for travellers going to places where the infection is common is generally considered to be low if the activities mentioned above are avoided.

Your GP can arrange for you to have a blood test to check for hepatitis B and have the hepatitis B vaccination if you're at a high risk.

High-risk areas

Hepatitis B is found throughout the world, but is particularly common in:

• sub-Saharan Africa
• east and southeast Asia
• the Pacific Islands
• parts of South America
• southern parts of eastern and central Europe
• the Middle East
• the Indian subcontinent

Most new cases of hepatitis B in the UK occur in people who caught the infection in one of these areas before moving to the UK.

Treatment for hepatitis B depends on how long you've been infected for:

• short-term (acute) hepatitis B doesn't usually need specific treatment, but may require treatment to relieve the symptoms
• long-term (chronic) hepatitis B is often treated with medication to keep the virus under control

Emergency treatment can also be given soon after possible exposure to the hepatitis B virus to stop an infection developing.

Emergency hepatitis B treatment

See your GP as soon as possible if you think you may have been exposed to the hepatitis B virus.

To help stop you becoming infected, they can give you:

• a dose of the hepatitis B vaccine – you'll also need two further doses over the next few months to give you long-term protection
• hepatitis B immunoglobulin – a preparation of antibodies that work against the hepatitis B virus and can offer immediate but short-term protection until the vaccine starts to take effect

These are most effective if given within 48 hours after possible exposure to hepatitis B, but you can still have them up to a week after exposure.

Treatment for acute hepatitis B

If you're diagnosed with hepatitis B, your GP will usually refer you to a specialist, such as a hepatologist (liver specialist).

Many people don't have any troublesome symptoms, but if you do feel unwell, it can help to:

• get plenty of rest
• take over-the-counter painkillers, such as paracetamol or ibuprofen, for tummy (abdominal) pain
• maintain a cool, well-ventilated environment, wear loose clothing, and avoid hot baths or showers if itching is a problem
• take medication such as metoclopramide to stop you feeling sick and chlorphenamine to reduce itching – your doctor can give you a prescription for these if necessary

Most people recover completely in a couple of months, but you'll be advised to have regular blood tests to check that you're free of the virus and haven't developed chronic hepatitis B.

Treatment for chronic hepatitis B

If blood tests show that you still have hepatitis B after six months, your doctor may recommend medication to reduce the risk of complications of hepatitis B and regular tests to assess the health of your liver.

Treatment is usually offered if:

• your immune system is unable to control the hepatitis B by itself
• there's evidence of ongoing liver damage

Hepatitis B medications can help keep the virus under control and stop it damaging your liver, although they won't necessarily cure the infection and some people need lifelong treatment.

The main medicines for chronic hepatitis B are outlined below.

Peginterferon alfa-2a

If your liver is working fairly well, the first treatment offered is usually a medicine called peginterferon alfa 2-a.

This stimulates the immune system to attack the hepatitis B virus and regain control over it. It's usually given by injection once a week for 48 weeks.

Common side effects include flu-like symptoms, such as a fever and muscle and joint pain, after you start to take the medicine, although these should improve with time.

Tests will be carried out during treatment to see how well it's working. Alternative medicines may be recommended if it's not helping.

Antiviral medicines

If your liver isn't working well, or peginterferon alpha-2a is not suitable or not working for you, your doctor may recommend trying antiviral medication instead.

This will usually be either tenofovir or entecavir, both of which are taken as tablets.

Common side effects of these medicines include feeling sick, vomiting and dizziness.

Living with hepatitis B

If you have hepatitis, you should:

• avoid having unprotected sex – including anal and oral sex, unless you're sure your partner has been vaccinated against hepatitis B
• avoid sharing needles used to inject drugs with other people
• take precautions to avoid the spread of infection – such as not sharing toothbrushes or razors with other people; close contacts such as family members may need to be vaccinated
• eat a generally healthy, balanced diet – there's no special diet for people with hepatitis B
• avoid drinking alcohol – this can increase your risk of developing serious liver problems
• speak to your doctor if you're thinking of having a baby

People with hepatitis B can usually have a healthy pregnancy, but it's a good idea to discuss your plans with a doctor first as you may need extra care and your medications may need to be changed.

There's a risk of pregnant women with hepatitis B passing the infection on to their child around the time of the birth, but this risk can be reduced by ensuring the baby is vaccinated shortly after they're born.

People with hepatitis B can sometimes develop serious liver problems. These mostly affect people with an untreated long-term (chronic) infection.

Some of the main problems associated with hepatitis B are outlined below.

Cirrhosis

Scarring of the liver (cirrhosis) affects around one in five people with chronic hepatitis B, often many years after they first got the infection.

Cirrhosis doesn't usually cause any noticeable symptoms until extensive damage to the liver has occurred, when it can cause:

• tiredness and weakness
• loss of appetite
• weight loss
• feeling sick
• very itchy skin
• tenderness, pain, or swelling in the tummy
• swelling of the ankles

There's currently no cure for cirrhosis, although it's possible to manage the symptoms and slow its progression. If the liver becomes severely damaged, a liver transplant may be needed.

Read more about the treatments for cirrhosis.

Liver cancer

People with cirrhosis caused by hepatitis B have around a 1 in 20 chance of developing liver cancer every year.

Symptoms of liver cancer include:

• unexplained weight loss
• loss of appetite
• feeling very full after eating, even if the meal was small
• feeling and being sick
• yellow skin and eyes (jaundice)

Treatment for liver cancer may involve surgery to remove the affected section of liver, a procedure to destroy the cancerous cells, or a liver transplant.

Read more about the treatments for liver cancer.

Fulminant hepatitis B

In less than 1 in 100 cases, short-term (acute) hepatitis B can lead to a serious problem called fulminant hepatitis B.

This is where the immune system attacks the liver and causes extensive damage to it.

It can lead to symptoms such as:

• confusion
• collapsing
• swelling of the tummy caused by a build-up of fluid
• severe jaundice

Fulminant hepatitis B can cause the liver to stop working properly and is often fatal if not treated quickly.