[The epidemiology and screening of hepatitis D]

Hepatitis D virus (HDV) is a defective RNA virus with 8 genotypes, which requires hepatitis B virus (HBV) for its replication both in co-infection (HDV infection occurs when people become infected with both hepatitis B and D simultaneously) and super-infection (HDV infection after infected with hepatitis B). Due to persistency of anti-HDV in the superinfected patient, the most epidemiology data of HDV infection suggests HBV/HDV super-infection. Because of inadequate awareness and effective HBV vaccination programme, HDV infection screen was not specific recommended, except for risk population recommended by AASLD. However, the disease burden of HDV infection was not fully understood and might be underestimated. This review summarized the anti-HDV and HDV genotype epidemiology and the screening of HDV infection.