What are the transmission routes of the hepatitis B virus?

China has a high prevalence of hepatitis B, with a large number of patients. Many individuals may unknowingly discover abnormal liver function during routine health check-ups, and only upon further testing learn they are infected with hepatitis B—prompting questions about how the infection occurred. So, what are the transmission routes of the hepatitis B virus (HBV)?

What Are the Transmission Routes of Hepatitis B Virus?

The primary transmission routes of HBV include bloodborne transmission, commonly occurring through sharing unsterilized syringes, intravenous drug use, or tattooing. Transmission via body fluids includes sexual contact. Small amounts of HBV can be detected in vaginal secretions or semen; thus, both hepatitis B and hepatitis C can be transmitted sexually. HBV may also be transmitted via saliva and breast milk. Mother-to-child (vertical) transmission remains the most common route in China. When a pregnant woman is infected with HBV, inadequate antenatal and perinatal prevention measures may result in viral transmission to the newborn. Due to the infant’s immature immune system, the virus cannot be effectively cleared, leading to persistent viral latency and chronic HBV infection.

Infection with HBV is not inherently life-threatening. Regular screening—including the “five-item hepatitis B panel” (HBsAg, anti-HBs, HBeAg, anti-HBe, and anti-HBc) or the “two-and-a-half panel”—is recommended. The presence of hepatitis B surface antibody (anti-HBs) significantly reduces the risk of infection—even upon exposure to contaminated items. However, anti-HBs titers gradually decline over time; therefore, periodic monitoring is essential.

As this disease is contagious, appropriate preventive measures should be adopted in daily life. We hope this information is helpful to you! Wishing you good health and happiness!