Epidemiological characteristics of hand-foot-mouth disease before and after the introduction of EV71 vaccine in Baiyun District, Guangzhou

Objective To explore the influence of EV71 vaccine on the epidemiological characteristics of hand-foot-mouth disease (HFMD) in Baiyun District, and we develop prevention and control strategies. Methods Hand-foot-mouth disease (HFMD) report information and EV71 vaccine data were obtained from the Chinese Disease Prevention and Control Information System and the Childhood Immunization Program Information System, and descriptive epidemiological analysis was conducted. Results A total of 83 574 cases of HFMD were reported from 2014 to 2019, among which 5 309 cases were laboratory diagnosed, with an average annual incidence of 573.85 / 100 000. After vaccination, the incidence of HFMD decreased from 2016 to 2018, but increased slightly in 2019. The annual time distribution showed bimodal prevalence, which was high in summer and autumn. The regional distribution was characterized by high population density and high incidence of towns and streets. The population distribution was more male than female, mainly occurred in children under 5 years old, and children living in diaspora were the majority. No significant changes were observed in the high incidence season, high-risk population and high incidence area. In terms of etiological characteristics, the dominant pathogens were other enterovirus and the composition ratio of EV71 generally showed a downward trend. From 2016 to 2019, a total of 287 375 doses of EV71 vaccine were administered in Baiyun District. Conclusion The overlap of EV71 vaccination peak and HFMD incidence peak reflects the low vaccination level of EV71 vaccine and the weak vaccination awareness of the public in Baiyun District, so the effect of controlling EV71 infection of HFMD is still limited. The high incidence was found in urban villages, which may be related to factors such as large population migration, high residential density and poor health awareness. The high incidence was among children under 5 years old, which may be related to low immunity level, unformed hygiene habits, and more exposure opportunities. Therefore, it is necessary to promote health education and health promotion in communities and families in order to improve the public awareness of vaccination and hygiene, improve the living and health environment, and form hygiene habits, so as to achieve the goal of comprehensive prevention and control of HFMD. 摘要：目的 探索广州市白云区EV71疫苗对手足口病流行病学特征影响, 为制定防控策略提供依据。 方法 通 过中国疾病预防控制信息系统与儿童免疫规划信息系统获取手足口病报告信息与EV71疫苗数据并进行描述性流行 病学分析。 结果 2014—2019年共报告手足口病病例83 574例, 其中实验室诊断病例共5 309例, 年平均发病率为 573.85/10万, EV71疫苗接种后2016—2018年手足口病发病率下降, 2019年略上升；时间分布上每年呈双峰流行, 具有 夏秋季高发的特点;地区分布上呈人群密集度高的镇街高发的特点;人群分布上男性多于女性 , 主要发生在5岁以下儿 童 , 散居儿童为主, 高发季节 、 高危人群及高发地区未见明显变化;病原学特征上优势病原体为其他肠道病毒, EV71构 成比总体呈下降趋势;2016—2019年白云区累计接种EV71疫苗287 375剂次。 结论 EV71疫苗接种高峰与手足口病 发病高峰重叠反映白云区EV71疫苗低接种水平、公众接种意识不强, 故控制EV71感染手足口病效果尚有限。城中村 为高发地点, 可能与人群流动性大、居住密度高、卫生意识差等因素有关。高发人群为5岁以下低龄儿童, 可能与免疫 力水平低、卫生习惯未形成、暴露机会多等因素有关。故需推动社区和家庭的健康教育与健康促进以提高公众的疫苗 接种意识与卫生意识、改善居住卫生环境、养成卫生习惯, 最终达到综合防控手足口病的目标。