2011—2018年上海市金山区手足口病病原学监测结果及柯萨奇病毒A6型分离株VP1基因特征分析

目的 了解2011—2018年上海市金山区手足口病病原学特征,分析柯萨奇病毒A6型(coxsackievirus A6, CoxA6)VP1基因特征,为手足口病防控提供理论依据。 方法 对2011—2018年金山区手足口病监测病原学检测情况进行统计分析。CoxA6病毒分离株进行VP1基因核苷酸序列测序,分析其同源性并构建系统进化树。 结果 2011—2018年金山区共采集手足口病例标本1 207例,病原学检测阳性703例,阳性率为58.24%(703/1 207);病原学构成为CoxA6 254例(36.13%)、CoxA16 217例(30.87%)、EV71 162例(23.04%)、CoxA10 18例(2.56%)和其他肠道病毒52例(7.40%)。2011—2013年,EV71、CoxA16、其他肠道病毒为优势病原;2014年起,CoxA6逐渐成为优势病原,2018年占病原学构成达85.43%。EV71发病呈单峰分布,高峰出现在5月;CoxA16呈双峰分布,主高峰出现在6月,次高峰出现在11月;CoxA6呈双峰分布,主高峰出现在11月,次高峰出现在7月。监测点监测2013年出现CoxA6型,疫情监测2014年出现CoxA6型。监测点监测,EV71,CoxA16和CoxA6病原年龄分布主要集中在1~5岁,其中CoxA6还主要集中在7~12岁。疫情监测,EV71、CoxA16、CoxA6病原分布主要集中在小班和中班,其中CoxA6病原分布还集中在小学。基因分析表明,2017—2018年金山区流行的CoxA6型病原基因特征为E2亚型。 结论 2011—2018年金山区手足口病的优势病原已由EV71、CoxA16转变为CoxA6 E2亚型为主。应进一步加强病原监测,尤其加强对7~12岁组病原的监测,及时发现新病原,为落实综合性防控手足口病预防措施提供依据。

Etiological surveillance results of hand,foot and mouth disease and genetic characteristics of VP1 from coxsackievirus A6 in Jinshan district of Shanghai, 2011-2018

Objective To investigate the etiological features of hand, foot and mouth disease (HFMD) in Jinshan district of Shanghai from 2011 to 2018, to analyze the genetic characteristics of VP1 gene of coxsackievirus A6 (CoxA6), and to provide a theoretical basis for HFMD prevention and control. Methods The pathogenic detection results of specimens of HFMD surveillance in Jinshan district during 2011-2018 were statistically analyzed. CoxA6 virus isolates were sequenced for VP1 nucleotide sequence, and homologous diseases were analyzed to construct phylogenetic tree. Results A total of 1,207 specimens of HFMD were collected in Jinshan district from 2011 to 2018. 703 cases were positive for etiology, with the positive rate of 58.24% (703/1,207). The main pathogenic viruses were CoxA6 (36.13%, 254/703), CoxA16 (30.87%, 217/703), EV71 (23.04%, 162/703), CoxA10 (2.56%, 18/703) and other enteroviruses (7.40%, 52/703). EV71, CoxA16 and other enteroviruses were the dominant pathogens in 2011-2013. CoxA6 gradually became the dominant pathogen from 2014, accounting for 85.43% of the total pathogenic composition in 2018. The incidence of EV71 showed a single peak distribution, and the peak appeared in May. CoxA16 showed a double peak distribution, the main peak appeared in June and the second peak in November. CoxA6 showed a double peak distribution, the main peak appeared in November and the second peak in July. Results from the monitoring point indicated that CoxA6 type appeared in 2013, whereas results from the epidemic monitoring showed that CoxA6 type appeared in 2014. Results from the monitoring point displayed that the age distribution of EV71, CoxA16 and CoxA6 pathogens was mainly concen-trated in 1-5 years old, of which CoxA6 was mainly concentrated in 7-12 years old. Results from the epidemic surveillance displayed that the distribution of EV71, CoxA16 and CoxA6 pathogens was mainly concentrated in primary classes and middle classes, of which CoxA6 was mainly concentrated in primary schools. Genetic analysis indicated that the CoxA6 pathogen gene prevalent in Jinshan district in 2017-2018 was characterized by the E2 subtype. Conclusions The dominant pathogen of HFMD in Jinshan district in 2011-2018 had been transferred from EV71 and CoxA16 to CoxA6 E2. Pathogen surveillance should be further strengthened, especially in the 7-12 year-old group. New pathogens should be found in time so as to provide a basis for implementing comprehensive prevention and control measures against HFMD.