Key facts

• Hepatitis B is a viral infection that attacks the liver and can cause both acute and chronic disease.
• The virus is most commonly transmitted from mother to child during birth and delivery, in early childhood, as well as through contact with blood or other body fluids during sex with an infected partner, unsafe injections or exposures to sharp instruments.
• WHO estimates that 240 million people were living with chronic hepatitis B infection in 2024, with 0.9 million new infections each year.
• In 2024, hepatitis B resulted in an estimated 1.1 million deaths, mostly from cirrhosis and hepatocellular carcinoma (primary liver cancer).
• Hepatitis B can be prevented by vaccines that are safe, available and effective.