Surveillance, epidemiology, and impact of the coronavirus disease 2019 interventions on the incidence of enterovirus infections in Nanchang, China, 2010-2022

Xianfeng Zhou; Ke Qian; Chunlong Zhu; Liu Yi; Junling Tu; Shu Yang; Yanxia Zhang; Yanglin Zhang; Wen Xia; Xiansheng Ni; Tielong Xu; Fenglan He; Hui Li

doi:10.3389/fmicb.2023.1251683

Surveillance, epidemiology, and impact of the coronavirus disease 2019 interventions on the incidence of enterovirus infections in Nanchang, China, 2010-2022

Front Microbiol. 2023 Oct 18:14:1251683. doi: 10.3389/fmicb.2023.1251683. eCollection 2023.

Authors

Xianfeng Zhou^{1

2}, Ke Qian², Chunlong Zhu³, Liu Yi², Junling Tu², Shu Yang², Yanxia Zhang², Yanglin Zhang³, Wen Xia², Xiansheng Ni², Tielong Xu⁴, Fenglan He², Hui Li²

Affiliations

¹ Cancer Research Center, Jiangxi University of Chinese Medicine, Nanchang, China.
² Jiangxi Provincial Health Commission Key Laboratory of Pathogenic Diagnosis and Genomics of Emerging Infectious Diseases, Nanchang Center for Disease Control and Prevention, Nanchang, China.
³ Clinical Laboratory, Third Hospital of Nanchang, Nanchang, China.
⁴ School of Life Science, Jiangxi University of Chinese Medicine, Nanchang, China.

Abstract

Introduction: Pathogen spectrum of Hand, foot and mouth disease (HFMD) has substantially changed in the past decade in China. Growing evidence has indicated that anti-COVID-19 nonpharmaceutical interventions (NPIs) can support control of various infectious diseases, including intestinal diseases.

Methods: In this study, HFMD cases were enrolled from sentinel hospitals of Nanchang, Jiangxi province, and enteroviruses were genotyped using specific real time RT-PCR. We systematically characterized the epidemiology of HFMD based on the continuous molecular surveillance and estimated the impact of COVID-19 intervention on HFMD incidence using seasonal autoregressive integrated moving average (ARIMA) models.

Results: A total of 10247 HFMD cases were included during 2010-2022, of which 6121 enterovirus (EV)-positive cases (59.7%) were identified by real-time RT-PCR. Over 80% cases were associated with EV-A71 and coxsackievirus A16 (CVA16) during 2010-2012, while the type distribution significantly changed as CVA6 emerged to be dominant, accounting for 22.6%-59.6% during 2013-2022. It was observed that the prevalence patterns of EV-A71 and CVA16 were similar and both of them peaked in the second quarter and then leveled off. However, CVA6 was generally prevalent around the fourth quarter, demonstrating a staggered prevalence during 2010-2019. During the COVID-19 epidemic, the seasonal HFMD epidemic peak was restrained, and the ARIMA analysis indicated that the COVID-19 intervention had mitigated EV transmission during the first COVID-19 outbreak in early 2020. In addition, bivariate Spearman's cross-correlation coefficients were estimated for the major types CVA6, CVA16 and EV-A71. Our analyses indicated the possible existence of correlations among CVA6, CVA16 and EV-A71 prevalence in the epidemiological level.

Discussion: Taken together, the type distribution of HFMD has substantially changed over the last decade and CVA6 and CVA16 are currently the most predominant types co-circulating in Nanchang. The anti-COVID-19 NPIs significantly reduced the incidence of EV infections.

Keywords: ARIMA; COVID-19; HFMD; enteroviruses; phylogenetic analysis; seasonality.

Grants and funding

The work was supported by National Natural Science Foundation of China (grant number 32360003), by grants from Science and Technology Bureau of Nanchang City, China (grant number 2020-133-17 to XZ, 2020KJZCHTS to SY), and by grants from Science and Technology Department of Jiangxi Province, China (grant number 20202BBGL73053 to FH).