Hepatitis B

Hepatitis B (sometimes called hep B) is a viral infection that attacks the liver. It can be passed on through sex, through contact with infected blood, or from a mother to her baby during birth. There's a vaccine that protects against it, and in the UK it's part of the routine childhood immunisation programme — so most young people are already vaccinated.

• Hepatitis B is a virus that infects the liver.
• It's transmitted through blood, semen, vaginal fluid, and from mother to baby.
• Most people in the UK have been vaccinated against it as babies (the vaccine was added to the routine schedule in 2017). [CHECK: exact year added to UK schedule]
• Many people with hepatitis B have no symptoms but can still pass it on.
• It can be acute (short-term) or chronic (long-term). Chronic hepatitis B can cause serious liver damage over time.

How it spreads

Hepatitis B is found in blood, semen, and vaginal fluid. It can be passed on through:

• Unprotected vaginal, anal, or oral sex with someone who has it
• Sharing needles or equipment for injecting drugs
• Contact with infected blood through a cut or wound
• From mother to baby during childbirth
• Sharing items that might have blood on them, like razors or toothbrushes

It's much more infectious than HIV — the virus can survive outside the body for at least 7 days and is found in higher concentrations in blood. You can't catch it from casual contact, kissing (unless there are blood-related sores), sharing food, or using the same toilet.

Symptoms

Many people with hepatitis B don't get symptoms, especially at first. When symptoms do appear, they can include tiredness, nausea, loss of appetite, stomach pain, dark urine, yellowing of the skin and eyes (jaundice), and joint pain. Symptoms can take 1-6 months to show up after infection.

In most adults, the immune system clears the virus within a few months (acute infection). But in some people — especially those infected as babies or young children — it becomes a long-term (chronic) infection that can quietly damage the liver over years, potentially leading to cirrhosis or liver cancer.

The vaccine

The hepatitis B vaccine is very effective and has been part of the UK's routine childhood vaccination programme since 2017, given as part of the 6-in-1 vaccine at 8, 12, and 16 weeks old. [CHECK: current schedule] If you were born before this was introduced and haven't been vaccinated, you can still get it — it's available free on the NHS for people at higher risk, and from sexual health clinics.

Things people get wrong

"Hepatitis B isn't an STI." It can be — sexual contact is one of the main routes of transmission. It's often grouped with other STIs in sexual health screening.

"If I was vaccinated as a baby, I'm definitely still protected." The vaccine provides long-lasting protection, and most people don't need a booster. But if you're in a higher-risk situation, a blood test can check whether your immunity is still strong. [CHECK: current booster guidance]

"It's not that serious." Acute hepatitis B usually clears on its own, but chronic hepatitis B can cause serious long-term liver damage. Getting vaccinated is the best protection.

Things people ask about hepatitis B

Am I already vaccinated?

If you were born in the UK after 2017, you almost certainly were — it's part of the routine baby vaccinations. If you're not sure, your GP can check your records. If you weren't vaccinated, you can get it done.

Can condoms protect against it?

Yes — condoms significantly reduce the risk of sexual transmission. But since hepatitis B can also spread through blood contact, the vaccine is the most reliable protection.

Is there a cure?

There's no cure for chronic hepatitis B, but antiviral medications can manage it and reduce liver damage. Acute infections usually clear on their own. The vaccine prevents infection in the first place, which is why it's so important.

Where to get help

• Your GP — to check your vaccination status or get vaccinated.
• Sexual health clinics — offer hepatitis B testing and vaccination, especially for people at higher risk.
• British Liver Trust — information and support about hepatitis and liver health.

Hepatitis B is a virus that infects the liver. It can be passed on through sex, through contact with someone's blood, or from a mother to her baby during birth.

Many people who have it don't feel ill at all, but they can still pass it on. When there are signs, they can include feeling very tired, feeling sick, tummy pain, dark wee, and the skin or eyes turning yellow.

In most adults, the body fights off the virus on its own within a few months. But in some people, the virus stays in the body long-term and can slowly damage the liver over years.

The good news is there's a vaccine that works very well. Most people born in the UK after 2017 were given it as babies. If you're not sure whether you've had it, your doctor can check. If you haven't, you can still get it.

Using condoms during sex helps lower the risk. But because the virus can also spread through blood, the vaccine is the best protection.

Hepatitis B is much more catching than some other infections. The virus can survive outside the body for days. You can't catch it from sharing food, hugging, or using the same toilet.