Epidemiology of hepatitis D

Area of Science:

• Hepatology
• Virology
• Public Health

Background:

• Hepatitis D virus (HDV) infection is a significant global health concern.
• HDV exclusively infects individuals already carrying the hepatitis B surface antigen (HBsAg), with approximately 5% of HBsAg carriers worldwide also infected by HDV.

Purpose of the Study:

• To analyze the global epidemiology of Hepatitis D.
• To highlight the impact of Hepatitis B vaccination on Hepatitis D incidence.
• To underscore the ongoing threat of HDV in regions with unchecked Hepatitis B Virus (HBV) prevalence.

Main Methods:

• Review of global epidemiological data on HDV and HBV.
• Analysis of trends in HDV incidence pre- and post-widespread HBV vaccination implementation.
• Assessment of the role of migration in HDV reintroduction.

Main Results:

• HDV incidence has declined in developed regions, particularly Southern Europe, following the introduction of HBV vaccination programs since the 1990s.
• Immigrants from HDV-endemic areas are contributing to the reintroduction of the infection in previously low-incidence regions.
• Hepatitis D continues to disproportionately affect populations in developing countries with high HBV prevalence.

Conclusions:

• HBV vaccination serves as a crucial preventive measure against both HBV and HDV infections.
• Continued efforts are needed to ensure widespread HBV vaccination, especially in developing nations, to combat the persistent burden of HDV.
• Addressing HBV in endemic regions is paramount to controlling HDV transmission globally.