2010年海南省手足口病流行病学和病原学特征分析

Epidemiology and Etiology of Hand-foot-and-mouth Disease in Hainan,2010

为了探究2010年海南省手足口病(Hand-foot-and-mouth disease,HFMD)的流行病学及病原学特征,本研究对2010年海南省HFMD病例报告信息进行整理分析,并对2010年海南省18县市1346份HFMD病例临床标本进行肠道病毒(enterovirus,EV)实验室检测。核酸检测阳性标本进行EV分离和鉴定,对分离到的肠道病毒71型(Enterovirus 71,EV71)的VP1编码区全长基因进行扩增及序列测定,用Sequencher 5.0和MEGA 5.0等生物信息学软件基于VP1编码区进行EV71的分子流行病学分析。流行病学分析表明:全省18个县市均有病例报告,尤其以东北部县市高发,同时以4岁以下的婴儿为高发人群;而与全国大多省份流行规律不同的是其发病高峰期为9和10月份。实验室结果显示:EV71和CA16是引起2010年海南省HFMD流行的主要病原,但EV71感染在重症病例和死亡病例中占绝对优势。除此之外,还存在部分由其它EV感染引起的HFMD病例。分子流行病学分析提示:2010年海南省流行的EV71均属于C4a亚型,该亚型为我国近年来流行的优势基因型,同时进化分析提示至少存在3条传播链。本研究数据对阐明海南HFMD的流行传播规律,以进一步指导HFMD防控具有重要理论价值。

To reveal the epidemiological and pathogenic characteristics of Hand-foot-and-mouth disease （HFMD） in Hainan province in 2010, epidemiology data of HFMD reporting cases were analyzed, clinical specimens from 1346 HFMD cases were collected for enterovirus （EV） detection. Viral isolation was performed for EV nucleic acid positive samples. Complete VP1 encoding region of EVT1 were sequenced and analyzed with Sequencher （version 5.0） and MEGA software （version 5.0）. The epidemiology data showed that all 18 prefectures in Hainan had reporting cases during 2010, with higher incidence in the northeast; and the children less than 4 years old accounted for the majority of the suffered; the epidemic reached peak during September to October, which was different from other Provinces in China. The laboratory results indicated that EV71 and CA16 were identified as the major causative pathogens in Hainan in 2010, however, EV71 infection was absolutely dominant among severe and fatal cases. In addition, some HFMD cases were identified associated with other serotypes of EV infections. Molecular epidemiological analysis showed that all the EV71 strains belonged to C4a evolutionary branch, which is the dominant evolutionary branch in China in recent years, and at least three transmission chains existed. This study has an important information in clarifying the characteristics of epidemics and transmission of HFMD in Hainan, and to provide the guidance for HFMD prevention and control in the future.