2017–2022年中国口蹄疫流行状况分析

Epidemiological characteristics of foot-and-mouth disease in China between 2017 and 2022

摘要:

【目的】分析近年来中国口蹄疫流行和传播特点，研判口蹄疫流行趋势。【方法】以2017-2022年间中国报告发生的口蹄疫疫情为研究对象，从疫情的“三间分布”、生产环节分布、流行毒株分子流行病学分析及溯源等方面，对近6年的疫情情况进行系统梳理。【结果】2017-2022年间中国共有15个省份报告发生口蹄疫疫情54次。总体形势稳定：Asia 1型口蹄疫维持无疫状态；2019-2022年连续4年未发生A型口蹄疫疫情；田间以散发O型口蹄疫为主。六年间报告牛口蹄疫疫情36次，羊疫情1次，猪疫情17次。分子流行病学研究表明，O/Mya-98、O/Ind-2001、O/CATHAY、O/PanAsia和A/Sea-97这5个流行毒株同时流行，且与同时期周边国家（缅甸、老挝和越南等）口蹄疫毒株遗传关系密切。流行病学调查结果显示，疫情（尤其是牛疫情，占比66.7%）主要发生在流通（57%）、散养（32%）等免疫薄弱环节。【结论】对内强化疫苗免疫和流通动物管控，对外严防境外毒株传入仍是今后中国口蹄疫防控的重要任务。

Abstract:

[Objective] To reveal the epidemic state and transmission characteristics of foot-and-mouth disease (FMD) in China based on the data of FMD outbreaks during 2017-2022. [Methods] The spatial, temporal, and susceptible species distribution, the production chain distribution, and the molecular epidemiology and traceability of the epidemic strains in China were analyzed.[Results] A total of 54 FMD outbreaks were reported in 15 provinces between 2017 and 2022. The general situation of FMD in China was stable considering the zero outbreak of serotype Asia 1, no report of serotype A for consecutive four years (2019-2022), and sporadic occurrence of serotype O. During 2017-2022, 36 outbreaks of FMD were reported in cattle, one outbreak in sheep, and 17 outbreaks in pigs. There were five epidemic strains (O/Mya-98, O/Ind-2001, O/CATHAY, O/PanAsia, and A/Sea-97) simultaneously circulating in China, which were closely related to the FMDV strains in surrounding countries (e.g., Myanmar, Laos, and Vietnam) during this period. Epidemiological investigation suggested that the outbreaks (especially in cattle, which accounted for 66.7%) mainly occurred in long-distance transport (57%) and backyard (32%) with incomplete vaccination. [Conclusion] In the future, strengthening vaccination and preventing the introduction of foreign strains are still major measures for FMD prevention and control in China.