The unfinished success of hepatitis B control in Saudi Arabia: Concentrated burden in adult males and geographic notification hotspots in the post-vaccination era, 2019-2023.

BACKGROUND Following the 1989 universal infant vaccination mandate, Saudi Arabia achieved significant reductions in Hepatitis B Virus (HBV) prevalence. The spatiotemporal dynamics of HBV notifications were performed to identify the "unfinished success" of the national elimination program.

METHODS We conducted a retrospective analysis of national HBV notification data (2019-2023). Gini coefficients measured inequality while Pareto analysis identified high-concentration foci. Vaccination program impact (VPI) was estimated by comparing pediatric (0-14 years) to adult notification rates (NR). Population attributable fraction (PAF) and VPI modeled the leverage of targeted versus universal screening strategies.

RESULTS A 75.6-fold higher NR in adults (30.24/100,000) than children (0.40/100,000; P < 0.001) was observed, with a Gini of 0.43 indicating high age-based inequality. PAF showed 98.2% of the national burden is concentrated in adults (15+ years). VPI was 98.7% [95% CI: 98.1%-99.1%], preventing an estimated 2,507 pediatric cases in 2023. The national NR exhibited a V-shaped trajectory: a 50.7% decline during the COVID-19 pandemic followed by a complete rebound by 2023, identifying the decline as a surveillance artifact. Saudi males had a 1.5-fold higher NR than females (58.45 vs. 37.93/100,000; NR Ratio = 1.54; P < 0.001). Geographically, Pareto analysis confirmed 78.5% of the burden concentrated in four regions, with Jazan as the primary hotspot (NR: 72.53).

CONCLUSION While infant vaccination has reached diminishing returns against the adult reservoir, we propose pivoting to a "Precision Public Health" approach, prioritizing targeted screening and linkage-to-care for Saudi adult males within identified geographic hotspots.