Hepatitis B is an infection of the liver caused by a virus that's spread through blood and body fluids.
It often does not 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.
Many people with hepatitis B will not experience any symptoms and may fight off the virus without realising they had it.
If symptoms do develop, they tend to happen 2 or 3 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
- tummy pain
- yellowing of the skin and eyes (jaundice)
These symptoms will usually pass within 1 to 3 months (acute hepatitis B), although occasionally the infection can last for 6 months or more (chronic 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
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.
Treatment for hepatitis B depends on how long you have been infected for.
If you have been exposed to the virus in the past few days, emergency treatment can help stop you becoming infected.
If you have 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 have had the infection for more than 6 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.
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.
A vaccine that offers protection against hepatitis B is routinely available for all babies born in the UK.
It's also available for people at high risk of the infection or complications from it.
- 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
- people who receive regular blood or blood products, and their carers
You do not need to pay for the vaccine if your child is eligible to receive it as part of the routine childhood vaccination schedule, or they're born to a mother with hepatitis B.
Others may have to pay for it.
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 1 to 3 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