Hepatitis B: A dangerous disease affecting 240 million people can cause cirrhosis and cancer

Hepatitis B attacks the liver and can develop into either an acute or chronic infection. For millions of people, the danger is not immediate symptoms but the damage that can build over time, including cirrhosis and liver cancer.

The World Health Organization estimated that about 240 million people were living with chronic hepatitis B in 2024. The disease caused 1.1 million deaths, mainly through complications involving the liver.

The virus most often passes from mother to child during childbirth, through unprotected sex or through contact with contaminated blood. Sharing needles can transmit it, as can sharing personal items such as razors. Ordinary contact does not spread the infection: hugging, sneezing and using the same eating utensils are not listed as routes of transmission.

Many infected people, particularly children, initially show no symptoms. When symptoms appear, they commonly include jaundice, dark urine, severe tiredness and abdominal pain. The risk of chronic infection is highest in newborns, at about 95 percent, while it falls below 5 percent in adults.

Vaccination provides the strongest protection. The vaccine is described as safe and almost 100 percent effective, usually given in three doses beginning within 24 hours of birth. If a mother has hepatitis B, the newborn should receive the first vaccine dose and hepatitis B immunoglobulin within 12 hours. Blood tests identify viral antigens and antibodies, but only 27 percent of infected people know their diagnosis, according to the WHO. Acute hepatitis B has no specific drug treatment, while chronic infection can be controlled with antivirals such as tenofovir. Treatment is often lifelong and aims to slow liver damage and lower the risk of cancer rather than cure the infection.