Feasibility of eliminating adult hepatitis B in Guangdong by 2030: A modeling study.

Objectives: Eliminating hepatitis B remains challenging, especially in Guangdong, the region with China's highest burden. Predicting incidence, optimizing vaccination, and reducing illness are essential to meet the WHO goal of a 90 % reduction by 2030. Methods: Based on the HBV surveillance data from 2005 to 2022, disease clustering patterns, correlation between vaccination and incidence were determined. A six-compartment transmission model was established and validated by estimating infectivity using nonlinear least squares and polynomial fitting. Results: From 2005 to 2022, acute HBV cases in Guangdong declined from 7509 to 2,097, while chronic cases in adults aged ≥15 rose from 38,595 to 146,658. High-risk clusters remained in Guangzhou, Foshan, and Shenzhen. Infant vaccination was linked to reduced acute infections but had limited effect on chronic cases. By 2030, acute HBV infectivity is projected to reach 1872 cases, with 100,354 new chronic infections expected in adults. To meet the WHO 2030 elimination target, average recovery time for chronic carriers must be reduced from 40 years to 7.7 years. For full elimination, it should be shortened to 1.85 years. Conclusions: Infant vaccination curbed acute HBV in youth, but chronic cases in adults threaten elimination goals. Scaling therapies to accelerate chronic HBV recovery is urgent.