We appreciate Sorn and Rouse's insightful letter [1] highlighting the critical challenges of hepatitis B virus (HBV) immunity gaps and inadequate screening among healthcare workers in resource‐limited settings. These observations address important gaps in occupational health, especially in an endemic setting.
Our study evaluated the question of HBV immune dynamics from a different angle, examining patients with established chronic hepatitis B (CHB) infection to investigate whether temporal patterns in hepatitis B surface antigen (HBsAg) loss coincided with population‐level vaccination coverage [2]. While our study focuses on this specific population with chronic infection, the observations by Sorn and Rouse on healthcare worker immunity represent complementary but equally important questions regarding primary prevention and sustained immune protection.
As we acknowledge in our study, our ecological study design establishes temporal association rather than individual‐level causality. The observed increase in HBsAg loss during the vaccination period is intriguing, but alternative explanations, including temporal coincidence, remain possible. To move beyond our observations and strengthen mechanistic understanding, we envision that future prospective studies incorporating immunologic markers would be valuable.
Such studies might explore whether vaccine‐induced transient immune activation correlates with changes in HBV‐specific T cell response pathways and cytokine dynamics; longitudinal HBsAg and anti‐HBs kinetics in relation to individual‐level vaccination exposure; and whether biologic markers of immune activation temporally associate with HBsAg clearance. These investigations could help determine whether our findings reflect genuine vaccine‐induced enhancement of HBV control or represent coincidental temporal overlap.
We agree that understanding HBV immune responsiveness across diverse contexts, whether in patients with chronic infection or healthcare workers, is pivotal for informing public health strategy. Both population‐level temporal observations and mechanistic immunological investigations will likely be needed to fully address these questions.
The systematic approach to HBV screening and booster vaccination strategies in endemic settings that Sorn and Rouse advocate remains important. We hope that future studies will complement their important public health agenda and ultimately deepen our understanding of HBV immune dynamics across populations.
Author Contributions
Jonggi Choi: conceptualization, writing – review and editing, writing – original draft, investigation, methodology, validation, formal analysis, data curation. Raymond T. Chung: writing – review and editing, supervision, resources, funding acquisition.
Funding
This research was also supported by NIH U19 AI082630.
Conflicts of Interest
The authors declare no conflicts of interest.
Linked Articles
This article is linked to Choi et al papers. To view these articles, visit https://doi.org/10.1111/apt.70733 and https://doi.org/10.1111/apt.70806.
Choi J. and Chung R. T., “Letter: HBsAg Loss After COVID‐19 Vaccination: Implications for HBV Screening, Immunity Monitoring, and Health Worker Protection in LMICs. Authors' Reply,” Alimentary Pharmacology & Therapeutics 64, no. 5 (2026): 691–692, 10.1111/apt.70848.
Handling Editor: Rohit Loomba
Data Availability Statement
Data sharing not applicable to this article as no datasets were generated or analysed during the current study.
References
- 1. Sorn V. and Rouse I. L., “Letter: HBsAg Loss After COVID‐19 Vaccination: Implications for HBV Screening, Immunity Monitoring and Health Worker Protection in LMICs,” Alimentary Pharmacology & Therapeutics 64, no. 5 (2026): 689–690, 10.1111/apt.70806. [DOI] [PubMed] [Google Scholar]
- 2. Choi J., Carroll A., Nguyen V. H., et al., “Temporal Association Between COVID‐19 Vaccination and HBsAg Loss in Chronic Hepatitis B Infection: An Interrupted Time Series Analysis,” Alimentary Pharmacology & Therapeutics 65, no. 4 (2026): 517–526, 10.1111/apt.70733. [DOI] [PMC free article] [PubMed] [Google Scholar]
Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.
Data Availability Statement
Data sharing not applicable to this article as no datasets were generated or analysed during the current study.