The largest outbreak of hand; foot and mouth disease in Singapore in 2008: The role of enterovirus 71 and coxsackievirus A strains
ABSTRACT During 2008, Singapore experienced its largest ever outbreak of hand, foot and mouth disease (HFMD), resulting in 29686 cases, including four cases of encephalitis and one fatality.
A total of 51 clinical specimens from 43 patients with suspected HFMD at the National University Hospital, Singapore were collected for virus isolation and identification by reverse transcription polymerase chain reaction (RT-PCR) and sequencing.
Enteroviruses were identified in 34 samples (66.7%), with 11 samples (21.6%) being positive for enterovirus 71 (EV71). Other non-EV71 enteroviruses (including coxsackievirus A4, A6, A10, and A16) were identified in 23 samples (45.1%). The most prevalent virus serotypes were CA6, CA10, and EV71. CA6 and CA10 accounted for 35.3% of all HFMD cases, which may explain the high transmissibility and low fatality that characterized this unprecedented epidemic associated with relatively mild disease. Phylogenetic analyses of 10 circulating EV71 strains indicated that they belonged to two subgenogroups, i.e., B5 (80%) and C2 (20%). The VP1 sequences of the 2008 EV71 strains also exhibited continuous mutations during the outbreak, reflecting the relatively high mutation rate of the EV71 capsid protein, which may have implications for future vaccine development.
A safe and effective vaccine against EV71 is certainly warranted in view of its potential neurovirulence and its role in HFMD epidemics of recurring frequency with resultant fatalities in Asia, as well as other parts of the world.
SourceAvailable from: Long Chen[Show abstract] [Hide abstract]
ABSTRACT: We determined the complete genome sequence of a coxsackievirus A16 strain (CVA16/SZ29/CHN/2014) from a fatal case in Shenzhen, southern China, in 2014. The strain was assigned to subgenotype B1b based on phylogenetic analysis of the VP1 gene. Copyright © 2015 Chen et al.Genome Announcements 01/2015; 3(2). DOI:10.1128/genomeA.00391-15
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ABSTRACT: Hand, foot, and mouth disease (HFMD) is caused by human enteroviruses, especially by enterovirus 71 (EV71) and coxsackievirus A16 (CA16). Patients infected with different enteroviruses show varied clinical symptoms. The aim of this study was to determine whether the etiological spectrum of mild and severe HFMD changed, and the association between pathogens and clinical features. From 2009 to 2013, a total of 2,299 stool or rectal specimens were collected with corresponding patient data. A dynamic view of the etiological spectrum of mild and severe HFMD in Shenzhen city of China was provided. EV71 accounted for the majority proportion of severe HFMD cases and fatalities during 2009-2013. CA16 and EV71 were gradually replaced by coxsackievirus A6 (CA6) as the most common serotype for mild HFMD since 2010. Myoclonic jerk and vomiting were the most frequent severe symptoms. Nervous system complications, including aseptic encephalitis and aseptic meningitis were observed mainly in patients infected by EV71. Among EV71, CA16, CA6, and CA10 infection, fever and pharyngalgia were more likely to develop, vesicles on the hand, foot, elbow, knee and buttock were less likely to develop in patients infected with CA10. Vesicles on the mouth more frequently occurred in the patients with CA6, but less in the patient with EV71. Associations between diverse enterovirus serotypes and various clinical features were discovered in the present study, which may offer further insight into early detection, diagnosis and treatment of HFMD. J. Med. Virol. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.Journal of Medical Virology 05/2015; DOI:10.1002/jmv.24200 · 2.22 Impact Factor
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ABSTRACT: Increased incidence of hand, foot and mouth disease (HFMD) has been recognized as a critical challenge to communicable disease control and public health response. This study aimed to quantify the association between climate variation and notified cases of HFMD in selected cities of Shanxi Province, and to provide evidence for disease control and prevention. Meteorological variables and HFMD cases data in 4 major cities (Datong, Taiyuan, Changzhi and Yuncheng) of Shanxi province, China, were obtained from the China Meteorology Administration and China CDC respectively over the period 1 January 2009 to 31 December 2013. Correlations analyses and Seasonal Autoregressive Integrated Moving Average (SARIMA) models were used to identify and quantify the relationship between the meteorological variables and HFMD. HFMD incidence varied seasonally with the majority of cases in the 4 cities occurring from May to July. Temperatures could play important roles in the incidence of HFMD in these regions. The SARIMA models indicate that a 1° C rise in average, maximum and minimum temperatures may lead to a similar relative increase in the number of cases in the 4 cities. The lag times for the effects of temperatures were identified in Taiyuan, Changzhi and Yuncheng. The numbers of cases were positively associated with average and minimum temperatures at a lag of 1 week in Taiyuan, Changzhi and Yuncheng, and with maximum temperature at a lag of 2 weeks in Yuncheng. Positive association between the temperature and HFMD has been identified from the 4 cities in Shanxi Province, although the role of weather variables on the transmission of HFMD varied in the 4 cities. Relevant prevention measures and public health action are required to reduce future risks of climate change with consideration of local climatic conditions.PLoS neglected tropical diseases 03/2015; 9(3):e0003572. DOI:10.1371/journal.pntd.0003572 · 4.72 Impact Factor