Hepatitis B is a viral infection that affects the liver and can lead to serious health complications if left untreated. It is important to understand the causes of hepatitis B in order to prevent its transmission and protect ourselves and others from this potentially life-threatening disease.

Hepatitis B is primarily caused by the hepatitis B virus (HBV), which is transmitted through contact with infected blood, semen, or other body fluids. The most common modes of transmission include:

1. Unprotected Sexual Contact: Engaging in unprotected sex with an infected person can put you at risk of contracting hepatitis B. The virus can be present in the semen, vaginal fluids, and blood of an infected individual.

2. Sharing Needles: Sharing needles or other drug paraphernalia with an infected person can lead to the transmission of hepatitis B. This is particularly common among intravenous drug users.

3. Mother-to-Child Transmission: Pregnant women infected with hepatitis B can pass the virus to their babies during childbirth. However, this risk can be significantly reduced through proper medical interventions, such as administering the hepatitis B vaccine to newborns.

4. Direct Contact with Infected Blood: Coming into contact with infected blood, such as through sharing personal items like razors or toothbrushes, can also lead to the transmission of hepatitis B.

Preventing the transmission of hepatitis B is crucial in reducing the burden of this disease.