Lombok Hepatitis B Model Immunization Project: toward universal infant hepatitis B immunization in Indonesia

Area of Science:

• Public Health
• Immunology
• Epidemiology

Background:

• Hepatitis B (HB) infection poses a significant global health challenge, particularly in endemic regions.
• Indonesia initiated the Lombok Hepatitis B (HB) Model Immunization Project, the nation's first mass infant immunization effort.
• Effective infant immunization strategies are crucial for preventing chronic HB infection and its sequelae.

Purpose of the Study:

• To evaluate the feasibility and impact of integrating a low-cost Hepatitis B (HB) vaccine into routine infant immunization services in Indonesia.
• To assess the effectiveness of early infant HB vaccination in reducing the prevalence of HB surface antigen.
• To determine the optimal timing for the first dose of HB vaccine to maximize protection.

Main Methods:

• Implementation of a mass infant HB immunization program in Lombok, Indonesia.
• Procurement of a low-cost HB vaccine and integration into existing Expanded Programme on Immunization (EPI) services.
• Delivery of the first HB vaccine dose within 1 week of birth for a subset of infants, with follow-up serological testing.

Main Results:

• Achieved >90% coverage for the three-dose HB vaccine series.
• Significantly reduced HB surface antigen prevalence from a baseline of 6.2% to 1.4% in infants receiving timely vaccination (first dose within 7 days).
• Infants receiving the first dose after 7 days showed a prevalence of 3.0%, indicating the importance of early vaccination.

Conclusions:

• Successful integration of the HB vaccine into the Indonesian EPI is feasible and strengthens routine immunization.
• Early administration of the first HB vaccine dose within 7 days of birth is critical for reducing chronic HB infection.
• The HB vaccine program significantly reduced chronic HB infection, particularly in infants born to HBe antigen-positive mothers.