Epidemiological Trends of HFMD in Jiangxi Province, China (2009–2022)

Overview

This retrospective analysis of HFMD in Jiangxi Province from 2009 to 2022 reveals distinct epidemiological shifts across three periods: pre-vaccination, post-EV-A71 vaccination, and post-vaccination combined with COVID-19 non-pharmaceutical interventions (NPI). The study highlights changes in incidence, pathogen distribution, and the impact of vaccination and NPI on disease dynamics.

Background

Hand, foot, and mouth disease (HFMD) is a contagious viral illness primarily affecting children under five, caused by enteroviruses such as EV-A71 and CVA16. While mostly mild, HFMD can lead to severe complications and fatalities, particularly with EV-A71 infections. China implemented an EV-A71 vaccine in 2016 and classified HFMD as a notifiable disease in 2008. The COVID-19 pandemic introduced NPIs that may have influenced HFMD transmission, but their combined effects with vaccination remain unclear. Jiangxi Province, a high-incidence region, provides a valuable setting to study these epidemiological trends.

Data Highlights

Key Findings

• HFMD incidence showed distinct temporal trends with a decline following EV-A71 vaccine introduction and a further reduction during COVID-19 NPIs.
• EV-A71 was the dominant pathogen pre-vaccination, with a shift towards other enteroviruses and CVA16 in later periods.
• Vaccination coverage increased steadily after 2016, contributing to reduced EV-A71-associated HFMD cases.
• COVID-19 NPIs implemented from 2020 led to decreased HFMD transmission, likely due to reduced social contact and enhanced hygiene.
• Age-specific analysis identified toddlers (1 year old) as the highest risk group, aligning with social behavior and exposure patterns.
• Advanced statistical models (Joinpoint regression, wavelet analysis, GLM, XGBoost) effectively characterized HFMD epidemiology and forecasted incidence trends.

Clinical Implications

The findings underscore the importance of sustained EV-A71 vaccination programs to reduce severe HFMD cases. Additionally, non-pharmaceutical interventions, such as those implemented during the COVID-19 pandemic, can effectively suppress HFMD transmission. Clinicians and public health officials should consider integrated strategies combining vaccination and behavioral interventions to control HFMD outbreaks, especially in high-incidence regions and vulnerable age groups.

Conclusion

This comprehensive analysis demonstrates that EV-A71 vaccination and COVID-19-related NPIs have significantly influenced HFMD epidemiology in Jiangxi Province. Integrated prevention strategies are essential to mitigate HFMD burden and guide future public health policies.

References

1. Zhang et al. 2023 -- Epidemiological Trends of Hand, Foot, and Mouth Disease Across Three Distinct Periods in Jiangxi Province, China: A Retrospective Analysis from 2009 to 2022