Hepatitis B

Hepatitis B is a viral infection of the liver that can cause both acute (short-term) and chronic (long-term) illness. It spreads through contact with infected blood or body fluids, including from mother to baby during birth. While many adults clear an acute infection completely, a proportion, particularly those infected as infants or young children, go on to develop chronic infection needing long-term management.

It is caused by the hepatitis B virus, transmitted through blood-to-blood contact, sexual contact, sharing needles, or from an infected mother to her baby during childbirth. Healthcare workers with needlestick injuries are also at some risk. Vaccination is highly effective at preventing infection through any of these routes.

Acute infection can cause fatigue, nausea, abdominal discomfort, and jaundice, though many people, especially children, have few or no symptoms during the initial infection. Chronic infection is often silent for years, with liver damage progressing gradually without obvious symptoms until more advanced stages. This is why testing, rather than waiting for symptoms, is important for anyone with risk factors.

Chronic hepatitis B carries a risk of long-term liver damage, including cirrhosis and liver cancer, over years to decades if untreated or unmonitored. With appropriate antiviral treatment and regular monitoring, this risk can be substantially reduced. Acute hepatitis B in adults usually resolves completely, though a small proportion go on to develop chronic infection.

Most adults who acquire hepatitis B clear the acute infection completely and develop lasting immunity. Chronic hepatitis B, however, is not generally curable with current treatments, though effective antiviral medication can suppress the virus to very low or undetectable levels, significantly reducing the risk of liver damage. Ongoing specialist monitoring remains important for anyone with chronic infection, even while on effective treatment.

Treatment for chronic hepatitis B, when needed, involves antiviral medication that suppresses viral replication and reduces liver inflammation and damage over time. Not everyone with chronic hepatitis B needs immediate treatment; some are monitored periodically if the virus and liver inflammation levels are low. A hepatologist or infectious disease specialist tailors the monitoring and treatment plan to individual test results.

Yes, vaccination is highly effective and is part of the routine UK childhood immunisation schedule, as well as being recommended for various at-risk adult groups. Safe sex practices, not sharing needles, and screening pregnant women (with preventive treatment for their babies if needed) also reduce transmission. Vaccination has dramatically reduced hepatitis B rates in countries where it is widely used.

Get tested if you have risk factors such as having lived in or travelled from a region with higher hepatitis B prevalence, unprotected sex with a new partner, shared needles, or a family member with hepatitis B. A private assessment including hepatitis B blood testing can typically be arranged within about one to two weeks. Pregnant women are routinely offered testing as part of antenatal care, since early identification allows preventive treatment for the baby.