百色市2014年手足口病流行病学特征分析

目的分析百色市2014年手足口病流行特征,探讨该病的预防控制策略。方法采用描述流行病学方法对百色市2014年手足口病发病特征进行流行病学分析。结果 2014年百色市共报告手足口病44 520例,年发病率为1 258.05/10万,死亡17例,病死率为0.04%。病例报告有明显的季节性,4-6月为发病高峰;以0~5岁年龄组为主,占95.39%;男性发病率高于女性,男女发病比为1.44∶1;职业分布以散居儿童居多;病原学监测结果为EV71、Cox A16和其他肠道病毒混合感染;79.04%的重症病例(含死亡病例)由EV71感染所致。结论百色市手足口病流行情况严重,EV71仍是引起手足口病重症病例和死亡的主要病原体,今后仍需要采取综合性防治措施,开展健康教育,加强重症病人的筛查和救治,降低病死率。     

新疆维吾尔自治区2008～2017年手足口病流行病学及病原学监测分析

分析2008～2017年新疆维吾尔手足口病流行病学和病原学特征。采用描述性流行病学的方法,对2008～2017年国家疾病监测信息报告管理系统报告的手足口病例和新疆手足口病网络实验室数据的进行分析。2008～2017年新疆累计报告手足口病例68 820例,重症107例,死亡10例,年均发病率为31.33/10万;病例主要集中在乌鲁木齐市、伊犁州、昌吉州和塔城地区,占总病例数68.26%;5月～7月为发病高峰,病例以1岁～4岁儿童为主,占总病例数的74.46%,散居儿童和幼托儿童分别占51.52%和40.34%;对12 345例手足口病例标本进行核酸检测,阳性8 872例,阳性率71.87%,普通病例中肠道病毒71型(EV-A71)、柯萨奇病毒A组16型(CV-Al6)和其他肠道病毒分别占33.01%、40.33%和26.65%,重症和死亡病例的病原型别均以EV-A71为主,分别占91.03%和100%。新疆1岁～4岁的儿童为手足口病主要发病人群,不同地区发病水平不同,手足口病病原谱呈现EV-A71、CV-A16和其他EV交替流行态势。     

濮阳市2008—2012年手足口病流行病学特征分析

目的了解濮阳市手足口病流行病学特征,为制定防控策略提供科学依据。方法通过国家疾病监测信息管理系统收集的全市2008—2012年6月6日手足口病疫情资料进行描述和分析,并对部分病例和重症病例标本进行肠道病毒病原学检测。结果全市共报手足口病16 492例,发病高峰是每年的3-5月(第12～20周),呈典型的单峰型曲线;发病年龄以0～4岁居多;男性多于女性;散居儿童多于托幼机构儿童,爆发病例多发生在托幼机构,手足口病病原有EV71、CoxA16和其他肠道病毒,以EV71和CoxA16为主。结论手足口病发病有明显的季节性、年龄和性别差异,小年龄组儿童是手足口病预防控制重点人群,流行年度和流行季节的优势毒株为EV71,重症患者中EV71占到86.35%;非流行年和季节手足病例主要由CoxA16和其他肠道病毒引起。手足口病防控重点应体现在对病例分类管理上,同时应继续加强重症病例疫情监测和爆发控制。     

2014—2015年泉州地区手足口病的流行特征及临床特点

目的 调查泉州地区手足口病（HFMD）流行的特征,为该地区HFMD的防治提供参考。方法 分析2014年9月至2015年9月泉州地区HFMD的发病季节、地区、性别、年龄及不同类型病毒感染的情况。结果 泉州地区一年四季均有新发HFMD病例,发病高峰在4~7月,次高峰为9~10月。发病人群以散居儿童多见;其中男性患者占64.9%,女性患者占35.1%,男女发病比例为1.9∶1,总体发病率为0.2%。患者中<5岁的儿童占94.9%,其中1~2岁占54.3%。脑炎病例多数患者年龄<2岁,尤其以1~2岁为多发。咽拭子标本检测发现,66.5%为EV71感染,6.8%为CoxA16感染,26.7%为其他病毒感染。多数病人有多处皮疹。结论 泉州地区HFMD病例在夏秋季明显增多,人口密集的地区发病率较高,以EV71感染最为多见。5岁以下儿童,特别是1~2岁儿童为HFMD易感人群。     

2011—2014年百色市重症手足口病流行病学及病原学分析

目的了解2011—2014年百色市重症手足口病的流行病学及病原学特点,为预防和控制重症手足口病提供依据。方法收集2011—2014年百色市重症手足口病疫情资料,进行描述性流行病学分析;采用实时荧光定量PCR方法对手足口病重症病例标本进行肠道病毒通用型、肠道病毒71型和柯萨奇病毒A16型核酸检测。结果2011—2014年百色市共报告手足口病105 900例,其中重症手足口病537例,重症率为0.51%;死亡35例,病死率为0.03%。重症手足口病发病主要集中在每年的4—5月;3岁以下重症病例占重症病例总数的88.27%,男女性别比为1.44∶1;散居儿童是主要的发病人群(75.98%);患者主要集中在平果县、田东县、田阳县、右江区等右江河谷一带;重症手足口病阳性患者中,肠道病毒71型占77.51%,柯萨奇病毒A16型占5.15%,其他肠道病毒占17.34%。结论 2011—2014年百色市重症手足口病多发于3岁以下的散居儿童,发病季节主要集中在4—5月,病原体以肠道病毒71型为主。     

1858例手足口病疫情监测分析

目的探讨手足口病疫情的流行特征。方法对我院2012年1～8月份报告的1858例手足口病患儿的临床资料进行回顾性分析。结果 1858例手足口病中,重症78例,死亡3例;重症病例咽、肛拭子采样检测,EV71感染76例,2例为其它肠道病毒感染;发病年龄3岁以下儿童占89%。发病男女性别比为1.62∶1;病例报告集中在5、6月份。结论在疫情流行期间加强手足口病防控工作及疫情监测,强化各级医务人员培训,早期识别重症患儿,可最大限度降低病死率。     

2010年海南省手足口病流行病学和病原学特征分析

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。     

炎琥宁联合痰热清治疗86例手足口病疗效观察及护理

近年来,手足口病的发病率有增多及严重的趋势,引起手足口病的肠道病毒包括肠道病毒71型（EV71）和A组柯萨奇病毒（CoxA）、埃可病毒（Echo）的某些血清型。EV71感染引起重症病例的比例较大,肠道病毒传染性强,可在短期内流行,我国小范围区域曾流行发病。临床上多采用病毒唑为主及加强对症治疗,为了寻找更有效的治疗方法,我科于2008年4～10月采用炎琥宁联合痰热清治疗手足口病86例,效果满意,现报告如下。     

2012‒2013年浙江省手足口病流行病学和病原学特征分析

摘要：目的 了解2012?2013年浙江省手足口病流行特征和病原构成,为手足口病防控工作提供参考。方法 收集2012?2013年浙江省手足口病疑似患者粪便、咽拭子、疱疹液标本,采用实时荧光RT-PCR对收集样本进行HFMD病原体检测。结果 2012?2013年共采集样本1 792例,患者以5岁以下散居儿童为主;浙江省手足口病发病高峰期在5~6月份,9月份出现发病次高峰;肠道病毒总检出率为72.9%,其中2012年浙江省手足口病优势病原体为EV71（40.3%）,其次为CoxA16（31.3%）,2013年浙江省手足口病优势病原体为其他肠道病毒（77.2%） （非EV71和CoxA16）,以CoxA6为主（51.3%）。不同样本类型中,肠道病毒检出率依次为疱疹液（100.0%）、粪便（76.2%）和咽拭子（65.1%）。结论 手足口病的流行具有季节性和人群性,不同年份引起手足口病的优势病原体存在变化,持续地病原监测有助于预防和控制手足口病的流行暴发。     

2007―2008年肠道病毒71型北京地区分离株的VP4基因序列分析

为了解2007 ― 2008 年北京地区流行的肠道病毒71 型( EV71) 是否存在基因序列变异及其与病毒毒力的关系, 我们选择2007 年分离的3 株EV71( 其中1 株分离自重症手足口病患儿的咽拭子标本, 其余2 株分离自普通手足口病患儿咽拭子标本) 和2008 年分离的5 株EV71( 其中3 株分离自重症手足口病患儿的咽拭子或鼻拭子标本, 2 株分离自普通手足口病患儿的疱疹液标本) , 提取基因组RNA, 经反转录-聚合酶链反应( RT-PCR) 扩增得到VP4 基因片段, 并进行核苷酸序列测定, 使用生物信息软件与GenBank 中的EV71 VP4 基因进行序列及病毒型别分析。结果表明, 所测得的8 株EV71 VP4 基因全长均为207 bp, 编码69 个氨基酸, 理论相对分子质量( Mr) 为7 ×10³。8 株EV71 病毒VP4 基因的核苷酸同源性在94% ～100% , 与GenBank 中其他EV71 病毒株VP4 的核苷酸同源性为82% ～100% , 与阜阳、深圳和台湾等地区流行的EV71 VP4 的核苷酸同源性比其他地区高。除了与印度报道的VP4 编码的氨基酸在第7 和54 位不同外( 印度株: 7 位蛋氨酸, 54位苏氨酸; 其余株7 位苏氨酸,54 位丙氨酸) , 这8 株EV71 VP4 编码的氨基酸序列之间以及与其他EV71 VP4编码的氨基酸同源性均为100%。8 株EV71 病毒VP4 与文献报道的3 株重症感染病毒株VP4 ( BrCr、MS 和NCKU9822) 核苷酸有较大差别, 而8 株病毒株中从重症感染( BJ97、BJ110B、BJ110Y 和BJ4243) 与轻症感染( BJ25、BJ47、BJ65 和BJ67) 分离到的毒株之间VP4 基因序列未见明显改变, 只有几个核苷酸存在差别。VP4 核苷酸序列的进化树分析表明, 这8 株EV71 均属于C4 亚型, 显示2007 ― 2008 年北京地区流行的EV71的VP4 基因相当保守, 分离自伴有神经系统感染的重症手足口病和普通手足口病患儿的EV71 的VP4 基因之间在核苷酸水平未出现同样的变异。结果提示, 近2 年来北京地区所流行的EV71 属C4 亚型。     

Characterization of an outbreak of hand, foot, and mouth disease in Nanchang, China in 2010

Recent outbreaks of human enterovirus 71 (EV71) infection and EV71-associated hand, foot, and mouth disease (HFMD) in China have affected millions and potentially lead to life-threatening complications in newborns. Furthermore, these outbreaks represent a significant global public health issue in the world. Understanding the epidemiology of HFMD and EV71 infection and their transmission patterns in China is essential for controlling outbreaks. However, no studies on the outbreaks of HFMD and EV71 infection in China during 2010 have been reported. In this report, we carried out an epidemiological analysis to study an outbreak of HFMD and EV71 infection in 2010 in the city of Nanchang in the Jiangxi province of People's Republic of China. From April 7 to May 11, 2010, a total of 109 HFMD cases were reported, and in this report the HFMD cases were studied by both epidemiological and laboratory analyses. The epidemiological study indicates that children aged younger than 8 years old represented more than 90% of the reported cases, with the age group of 1-3 years containing the highest number of cases. Laboratory studies detected a high prevalence of EV71 amongst the cases in our study, suggesting EV71 as a common enterovirus found in HFMD cases in Nanchang. Phylogenetic analysis of the sequence of the VP1 region of four EV71 isolates indicated that the Nanchang strains belong to the C4 subgenotype commonly found in China during outbreaks in 2008 but contain distinct variations from these strains. Our study for the first time characterizes the epidemiology of HFMD and EV71 infection in China in 2010 and furthermore, provides the first direct evidence of the genotype of EV71 circulating in Nanchang, China. Our study should facilitate the development of public health measures for the control and prevention of HFMD and EV71 infection in at-risk individuals in China.     

Epidemiological Characteristics and Spatial-Temporal Clusters of Hand,Foot, and Mouth Disease in Zhejiang Province,China, 2008-2012

Hand, foot and mouth disease (HFMD) is one of the major public health concerns in China. Being the province with high incidence rates of HFMD, the epidemiological features and the spatial-temporal patterns of Zhejiang Province were still unknown. The objective of this study was to investigate the epidemiological characteristics and the high-incidence clusters, as well as explore some potential risk factors. The surveillance data of HFMD during 2008–2012 were collected from the communicable disease surveillance network system of Zhejiang Provincial Center for Disease Control and Prevention. The distributions of age, gender, occupation, season, region, pathogen’s serotype and disease severity were analyzed to describe the epidemiological features of HFMD in Zhejiang Province. Seroprevalence survey for human enterovirus 71 (EV71) in 549 healthy children of Zhejiang Province was also performed, as well as 27 seroprevalence publications between 1997 and 2015 were summarized. The spatial-temporal methods were performed to explore the clusters at county level. Furthermore, pathogens’ serotypes such as EV71 and coxsackievirus A16 (Cox A16) and meteorological factors were analyzed to explore the potential factors associated with the clusters. A total of 454,339 HFMD cases were reported in Zhejiang Province during 2008–2012, including 1688 (0.37%) severe cases. The annual average incidence rate was 172.98 per 100,000 (ranged from 72.61 to 270.04). The male-to-female ratio for mild cases was around 1.64:1, and up to 1.87:1 for severe cases. Of the total cases, children aged under three years old and under five years old accounted for almost 60% and 90%, respectively. Among all enteroviruses, the predominant serotype was EV71 (49.70%), followed by Cox A16 (26.05%) and other enteroviruses (24.24%) for mild cases. In severe cases, EV71 (82.85%) was the major causative agent. EV71 seroprevalence survey in healthy children confirmed that occult infection was common in children. Furthermore, literature summary for 26 seroprevalence studies during 1997–2015 confirmed that 0–5 years group showed lowest level of EV71 seroprevalence (29.1% on average) compared to the elder children (6–10 years group: 54.6%; 11–20 years group: 61.8%). Global positive spatial autocorrelation patterns (Moran’s Is>0.25, P<0.05) were discovered not only for mild cases but also for severe cases, and local positive spatial autocorrelation patterns were revealed for counties from the eastern coastal and southern regions. The retrospective space-time cluster analysis also confirmed these patterns. Risk factors analyses implied that more EV71 and less sunshine were associated with the clusters of HFMD in Zhejiang Province. Our study confirmed that Zhejiang Province was one of the highly epidemic provinces in China and that the epidemiological characteristics of HFMD were similar to other provinces. Occult infection in elder children and adults was one of the important reasons why most HFMD cases were children aged under-five. Combining the results of spatial autocorrelation analysis and the space-time cluster analysis, the major spatial-temporal clusters were from the eastern coastal and southern regions. The distribution of pathogens’ serotypes and the level of sunshine could be risk factors for, and serve as an early warning of, the outbreak of HFMD in Zhejiang Province.     

Phylogenetic Analysis of Enterovirus 71 Circulating in Beijing,China from 2007 to 2009

The major pathogens of hand, foot and mouth disease (HFMD) in Beijing, China from 2007 to 2009 were identified in this study. A total of 186 HFMD cases were included, and 136 cases (73%) were positive for enterovirus (EV). In 2007, 75% (27/36) were Coxsackievirus A16 (CA16) positive and 19% (7/36) were Enterovirus 71 (EV71) positive cases. However, EV71 was the predominant virus in 2008, when 56% (31/55) of the cases were positive for EV71 and 22% (12/55) were positive for CA16. In 2009, EV71 and CA16, with positive rates of 36% (16/45) and 29% (13/45), respectively, were still the major pathogens of HFMD. Phylogenetic analysis revealed that the dominant genotype of EV71 was C4, with co-circulation of genotype A in 2009. The prevalent cluster of the EV71 subgenotype C4 changed over time. A proposed new sublineage of EV71, C4a-2, was the predominant virus associated with the Beijing and nationwide HFMD outbreaks since 2008 and amino acid substitution, which possibly link to the central nervous system tropism of EV71, was found in genotype A viruses. Persistent surveillance of HFMD-associated pathogens is required for predicting potential emerging viruses and related disease outbreaks.     

Population Dynamics and Genetic Diversity of C4 Strains of Human Enterovirus 71 in Mainland China, 1998–2010

Background

Since 1997, several countries within the Asian Pacific region have been affected by one or more massive outbreaks of Hand Foot and Mouth Disease (HFMD). Virus typing experiments revealed that these outbreaks were caused by strains of human enterovirus 71 (EV71) belonging to several different, recently emerged subgenogroups. In mainland China, a different situation was observed. The first outbreak, localized in Shangdong Province, was reported in 2007, and was followed by a wide-spread outbreak in mainland China in 2008. Since then, numbers of reported HFMD cases have been persistently high.

Methodology/Principal Findings

To gain insight in the epidemiological behavior of EV71 in China, we studied genetic diversity and EV71 population dynamics to address whether the increase in number of reported EV71 infections reflects a real increase in viral spread or is just the result of increased awareness and surveillance. We used systematically collected VP1 gene sequences of 257 EV71 strains collected in Guangdong province from 2008 to 2010 as part of HFMD surveillance activities, and supplemented them with 305 GenBank EV71 reference stains collected in China from 1998 to 2010. All isolates from Guangdong Province belonged to subgenogroup C4. Viral population dynamics indicated that the increased reporting of HFMD in China since 2007 reflects a real increase in viral spread and continued replacement of viral lineages through time. Amino acid sequence comparisons revealed substitution of amino acid in residues 22, 145 and 289 through time regularly with the VP1 gene of EV71 strains isolated in mainland China from 1998 to 2010.

Conclusions

EV71 strains isolated in mainland China mainly belonged to subgenogroup C4. There was exponential growth of the EV71 virus population in 2007 and 2008. There was amino acid substitution through time regularly with the VP1 gene which possibly increased viral spread and/or ability of the virus to circulate persistently among the Chinese population.     

2009年上海市手足口病流行病学和病原学特征

本研究对上海市手足口病(Hand-foot-and-mouth disease,HFMD)的流行病学和病原学特征进行了分析。从国家疾病监测信息报告管理系统获取上海市2009年HFMD的流行病学数据;采用荧光定量RT-PCR方法对来自上海15个区县的799例HFMD进行肠道病毒(Enterovirus,EV)核酸检测;对部分肠道病毒71型(Enterovirus71,EV71)的VP1区和部分其它EV的VP4区序列进行测定和分析。采用Office excel软件进行简单数据统计分析,用BioEdit和MEGA软件进行病毒基因特征分析,通过BLAST服务器的在线比对进行EV型别鉴定。分析显示:上海市18个区县均有病例报告,地区分布无显著特点;小于6岁的婴幼儿期为疾病高发年龄段;4～7月为发病高峰期;EV71和柯萨奇病毒A16(Coxsackie virus A16,CA16)为主要病原,不同地区、不同月份的病原构成各不相同,CA16为轻症病例的主要病原,EV71则为重症病例的主要病原;基于VP1区序列分析,上海EV71毒株与C4a亚型毒株具有最近的亲缘性和最高的同源性;2株其它肠道病毒经鉴定属于CA2和CA10型。结果表明:EV71和CA16为2009年上海HFMD流行的主要病原,EV71属于C4a亚型;除EV71和CA16外,还存在小部分其它EV(如:CA2和CA10)引起的HFMD。     

Genotypes of the Enterovirus Causing Hand Foot and Mouth Disease in Shanghai,China, 2012-2013

Sporadic HFMD (hand foot and mouth disease, HFMD) cases and outbreaks caused by etiologic agents other than EV71 and CA16 have increased globally. We conducted this study to investigate the prevalence and genetic characteristics of enteroviruses, especially the non-EV71 and non-CA16 enteroviruses, causing HFMD in Shanghai. Clinical specimens were collected from patients with a diagnosis of HFMD. A partial length of VP1 was amplified with RT-PCR and subjected to direct sequencing. Phylogenetic analyses were performed using MEGA 5.0. The ages of the HFMD cases ranged from 3 to 96 months, and the male/female ratio was 1.41. The median hospital stay was 2.96 days. Up to 18.0% of patients had neurologic system complications such as encephalitis, meningoencephalitis or meningitis. Of the 480 samples, 417 were positive for enterovirus (86.9%) with RT-PCR. A total of 13 enterovirus genotypes were identified. The most frequent genotypes were CA6 (31.9%), EV71 (30.6%), CA16 (8.8%) and CA10 (7.5%). Infections with CA6, EV71, CA16 and CA10 were prevalent throughout the years of study, while the proportion of CA6 notably increased from Sep. 2012 to Dec. 2013. Phylogenetic analyses showed that EV71 strains belonged to the C4a subgenogroup and CA16 was identified as B1b subgenogroup. The CA6 strains were assigned to genogroup F, whereas the CA10 strains were assigned to genogroup D. Patients infected with CA6 were typically younger, had a shorter hospital stay and had a lower incidence of neurologic system complications when compared to patients infected with EV71. Our study demonstrates that the enterovirus genotypes causing HFMD were diversified, and there was an increasing prevalence of the non-EV71 and non-CA16 enteroviruses from 2012 to 2013. CA6 was the most predominant pathogen causing HFMD from Sep. 2012 to Dec. 2013, and it often caused relatively mild HFMD symptoms. Most severe HFMD cases were associated with EV71 infection.     

Hand foot and mouth disease due to enterovirus 71 in Malaysia

Hand foot and mouth disease is a febrile sickness complex characterized by cutaneous eruption (exanthem) on the palms and soles with simultaneous occurrence of muco-cutanous vesiculo-ulcerative lesions (enanthem) affecting the mouth.The illness is caused by a number of enteroviruses with coxsackievirus A16 and enterovirus 71 as the main causative agents.Human enterovirus 71 (EV71) belongs to the species Human enterovirus A under the genus Enterovirus within the family Picornaviridae.EV71 has been associated with an array of clinical diseases including hand foot and mouth disease (HFMD),aseptic meningitis,encephalitis and poliomyelitis-like acute flaccid paralysis.A large outbreak of HFMD due to highly neurovirulent EV71 emerged in Malaysia in 1997,and caused 41deaths amongst young children.In late 2000,a recurrence of an outbreak of HFMD occurred in Malaysia with S fatalities in peninsular Malaysia.Outbreak of HFMD due to EV71 recurred in 2003 with an unknown number of cases and mortalities.A similar outbreak of HFMD with 2 recorded deaths in young children occurred in peninsular Malaysia in late 2005 and this was followed by a larger outbreak in Sarawak (Malaysian Borneo) with 6 reported fatalities in the early part of 2006.The current on-going outbreak of HFMD started in peninsular Malaysia in epidemiological week 12 of 2010.As with other HFMD outbreaks in Malaysia,both EV71 and CA16 were the main aetiological viruses isolated.In similarity with the HFMD outbreak in 2005,the isolation of CA16 preceded the appearance of EV71.Based on the VP 1 gene nucleotide sequences,4 sub-genogroups of EV71 (C1,C2,B3 and B4) co-circulated and caused the outbreak of hand,foot and mouth disease in peninsular Malaysia in 1997.Two sub-genogroups (C1 and B4) were noted to cause the outbreak in 2000 in both peninsular Malaysia and Sarawak.EV71 of sub-genogroup B5 with smaller contribution from sub-genogroup C1 caused the outbreak in 2003.In the 2005 outbreak,besides the EV71 strains of sub-genogroup C1,EV71 strains belonging to sub-genogroup B5 were isolated but formed a cluster which was distinct from the EV71 strains from the sub-genogroup B5 isolated in 2003.The four EV71 strains isolated from clinical specimens of patients with hand,foot and mouth disease in the Sarawak outbreak in early 2006 also belonged to sub-genogroup B5.Phylogenetic analysis of the VP1 gene suggests that the EV71 strains causing the outbreak in Sarawak could have originated from peninsular Malaysia.Epidemiological and molecular data since 1997 show the recurrence of HFMD due to EV71 in Malaysia every 2 to 4 years.In each of the past outbreaks,more than one sub-genogroup of the virus co-circulate.