2019—2022年广西壮族自治区柳州市手足口病病原学监测及柯萨奇病毒A6型VP1基因特征

Pathogenic surveillance results of hand,foot and mouth disease and characteristics of VP1 gene of Coxsackievirus A6,in Liuzhou city,Guangxi Zhuang Autonomous Region,2019-2022

目的描述2019—2022年柳州市手足口病病原学监测结果,并对鉴定为柯萨奇病毒A6型(Cox A6)的VP1基因特征进行分析,以掌握本地区手足口病的病原组成以及Cox A6的分子流行病学特征。方法采集2019—2022年柳州市手足口病监测哨点医院诊断为手足口病患儿的肛拭子、咽拭子、疱疹液标本,采用荧光定量PCR的方法对病例标本进行病原学检测和分型检测,并对2019年部分重症病例中鉴定为Cox A6病毒分离株进行VP1基因测序并分析。结果2019—2022年柳州市共检测手足口病例标本1432份,病原学检测阳性1224份,阳性率为85.47%,其中Cox A6阳性547份(44.69%)、Cox A16阳性428份(34.97%)、EV71阳性22份(1.80%)、Cox A10阳性60份(4.90%)、其他肠道病毒阳性167份(13.64%)。6株2019年柳州市重症手足口病Cox A6毒株主要有3支,一支与2017年广东病毒分离株有较近的基因亲缘性关系,一支与2018年上海病毒分离株有较近的基因亲缘性关系,另一支则与2019年江西病毒分离株有较近的基因亲缘性关系。结论2019—2022年柳州市手足口病的病原体主要有Cox A6、Cox A16、Cox A10、其他肠道病毒,其中Cox A6已经成为柳州市手足口病的优势毒株。VP1基因之间核苷酸同源性为93.5%~100.0%,氨基酸同源性为98.3%~100.0%,均属于D基因型的D3基因亚型,应进一步加强病原监测,为落实综合性防控手足口病预防措施提供依据。

Objective To describe the pathogenic surveillance results of hand,foot and mouth disease(HFMD)in Liuzhou from2019 to 2022,analyze the characteristics of VP1 gene of Coxsackievirus A6(CoxA6)identified,and capture the pathogenic composition of HFMD and the molecular epidemiological characteristics of CoxA6 in the region.Methods Collect anal swab,pharyngeal swab,and herpes fluid samples from children diagnosed with HFMD at Liuzhou city Hand,Foot and Mouth Disease Monitoring Outpost Hospital from 2019 to 2022.Quantitative fluorescent PCR was used for the pathogen detection and typing;VP1 gene of CoxA6 isolates identified from some severe cases was sequenced and analyzed.Results From 2019 to 2022,a total of1432 samples from HFMD cases were collected in Liuzhou city,and 1224 were tested positive,with a positive rate of 85.47%.Of them,547(44.69%)were positive for CoxA6;428(34.97%)were positive for CoxA16;22(1.80%)were positive for EV71;60(4.90%)were positive for CoxA10 and 167(13.64%)were positive for other enteroviruses.The six CoxA6 isolates that caused severe HFMD in Liuzhou city in 2019 mainly included three strains,which were closely related to the strains identified in Guangdong in 2017,in Shanghai in 2018 and in Jiangxi in 2019,respectively.Conclusions CoxA6,CoxA16,CoxA10 and other enteroviruses are the main pathogens of HFMD in Liuzhou city from 2019 to 2022,and CoxA6 has become the dominant pathogen in Liuzhou city.The nucleotide homology of VP1 gene was from 93.5%to 100.0%,and the amino acid homology was from 98.3% to 100.0%,both belonging to the D3 gene subtype of D genotype.Pathogen monitoring should be further strengthened to provide a basis for implementing comprehensive prevention and control measures of HFMD.