What causes the liver infection known as hepatitis B?

Hepatitis B is caused by a virus known as the hepatitis B virus (HBV), which is primarily transmitted through exposure to infectious body fluids, including blood, semen, and other bodily secretions. This type of transmission can occur through a variety of means, such as unprotected sexual contact, sharing needles, or from mother to child during childbirth.

Understanding the mode of transmission is crucial in preventing the spread of hepatitis B. Vaccination is available and highly effective in preventing the infection, underscoring the importance of public health initiatives aimed at promoting awareness and immunization. The other options do not appropriately describe the nature or transmission method of hepatitis B, as it is specifically viral rather than bacterial, linked to vaccines, or caused by autoimmune factors.