Hepatitis B birth vaccination, cohort study, Tunisia 2000-2017

Area of Science:

• Immunology
• Public Health
• Epidemiology

Background:

• Hepatitis B (HB) remains a significant global health concern.
• Vaccination strategies are key to controlling HB transmission.
• Evaluating vaccine timing is crucial for optimizing public health outcomes.

Purpose of the Study:

• To compare the efficiency and efficacy of the first dose of the Hepatitis B (HB) vaccine administered at birth versus at 3 months of age.
• To assess the long-term impact of different HB vaccination schedules on disease incidence.
• To evaluate the contribution of the Hepatitis B Birth Dose (HepB-BD) to the World Health Organization's (WHO) HB elimination targets.

Main Methods:

• A cohort study was conducted in Monastir from January 2000 to December 2017.
• Two vaccination protocols were compared: Protocol 1 (first dose at 3 months) and Protocol 2 (first dose at birth - HepB-BD).
• Hepatitis B virus (HBV) infection was determined using serological markers (HBsAg and anti-HBc), and Absolute Risk (AR) and Relative Risk Reduction (RRR) were calculated.

Main Results:

• The HepB-BD protocol (Protocol 2) showed significantly higher efficacy, with an Absolute Risk (AR) of 0.11 per 100,000 PY compared to 5.67 in Protocol 1.
• The Relative Risk Reduction (RRR) was 99.4% for HepB-BD versus 77% for the 3-month schedule.
• Zero HB cases were observed in children aged 5-11 who received HepB-BD, compared to 4 cases in the same age group who received the first dose at 3 months.

Conclusions:

• The Hepatitis B vaccine administered at birth (HepB-BD) is highly effective (99.4%) in preventing Hepatitis B infections.
• Implementing HepB-BD globally is essential for achieving the WHO's goal of eliminating Hepatitis B as a public health threat by 2050.
• The study highlights the critical importance of early vaccination in reducing HB incidence and achieving elimination targets.