Enterovirus A71 (EV-A71) and coxsackievirus A16 (CV-A16) are closely related enteroviruses that cause hand, foot and mouth disease (HFMD) in children. Serious neurological complications almost always occur in EV-A71 infection, but are rare in CV-A16 infection. Based on the hypothesis that this may be because EV-A71 infects neuronal cells more easily than CV-A16, we compared virus infection, replication and spread of EV-A71 and CV-A16 in SK-N-SH cells. We found that CV-A16 invariably showed significantly lower replication and caused less necrotic cell death in SK-N-SH cells, compared with EV-A71. This was not due to a lower proportion of CV-A16-infected cells, since both viruses showed similar proportions of infected cells at all time points analyzed. Furthermore, reduced replication of CV-A16 in SK-N-SH cells does not appear to be due to limited viral receptor availability, which might limit viral entry, because experiments with viral RNA-transfected cells showed the same results as for live virus infections. On the other hand, no differences were observed between EV-A71 and CV-A16 in RD cells and results were generally similar in RD cells for both viruses. Taken together, our findings suggest that the poor growth of CV-A16 and EV-A71in SK-N-SH cells, compared with RD cells, may be due to cell type-specific restrictions on viral replication and spread. Furthermore, the lower viral replication and necrotic cell death in CV-A16-infected SK-N-SH cells, compared with EV-A71-infected SK-N-SH cells, is consistent with the lower prevalence of neurotropism observed in CV-A16-associated HFMD outbreaks. Nonetheless, in vivo data and more extensive comparisons of different viral strains are essential to confirm our findings.
Enterovirus 71 (EV-A71) is one of the major pathogens causing hand, foot and mouth disease (HFMD). Some strains can lead to neurological disease and fatality in children. Up to date, there is no FDA-approved vaccine to prevent severe HFMD and mortality. Although the inactivated vaccine has advanced to production in China, lack of long-term protection and the requirement of multiple boosters have necessitated the development of other types of vaccines. Recent studies indicate that cellular and not humoral immunity determines the clinical outcome of EV-A71 infections. High levels of cytokines such as IL-1β, IL-6, IL-10 and IFN-γ tend to correlate with clinical severity in patients with pulmonary edema and encephalitis. The live attenuated vaccine may serve as the preferred choice as it can induce excellent humoral and cellular immunity as well as live-long immunity. Expression of certain HLA alleles such as TNF-α promoter type II (-308 allele), HLA-A33 and HLA-DR17 responses have been linked to severe HFMD. However, the high variability of MHC genes could restrict T cell recognition and be a major obstacle in the design of peptide vaccines. Hence, the development of a T cell universal vaccine (incorporating both CD4+ and CD8+ T cell epitopes) that induces broad, multifunctional and cross-reactive CD8+ T cell responses maybe desirable.
Matched MeSH terms: Hand, Foot and Mouth Disease/immunology
Besides causing mild hand, foot and mouth infections, Enterovirus A71 (EV-A71) is associated with neurological complications and fatality. With concerns about rising EV-A71 virulence, there is an urgency for more effective vaccines. The live attenuated vaccine (LAV) is a more valuable vaccine as it can elicit both humoral and cellular immune responses. A miRNA-based vaccine strain (pIY) carrying let-7a and miR-124a target genes in the EV-A71 genome which has a partial deletion in the 5'NTR (∆11 bp) and G64R mutation (3Dp°l) was designed. The viral RNA copy number and viral titers of the pIY strain were significantly lower in SHSY-5Y cells that expressed both let-7a and miR-124a. Inhibition of the cognate miRNAs expressed in RD and SHSY-5Y cells demonstrated de-repression of viral mRNA translation. A previously constructed multiply mutated strain, MMS and the pIY vaccine strain were assessed in their ability to protect 4-week old mice from hind limb paralysis. The MMS showed higher amounts of IFN-γ ex vivo than the pIY vaccine strain. There was absence of EV-A71 antigen in the skeletal muscles and spinal cord micrographs of mice vaccinated with the MMS and pIY strains. The MMS and pIY strains are promising LAV candidates developed against severe EV-A71 infections.
Matched MeSH terms: Hand, Foot and Mouth Disease/diagnosis; Hand, Foot and Mouth Disease/immunology; Hand, Foot and Mouth Disease/prevention & control*; Hand, Foot and Mouth Disease/virology
The Hand, Foot and Mouth Disease (HFMD) is caused by Enterovirus 71 (EV-A71) and Coxsackieviruses. Common HFMD symptoms are high fever (≥ 39°C), rashes, and ulcers but complications due to virulent EV-A71 may arise leading to cardiopulmonary failure and death. The lack of vaccines and antiviral drugs against EV-A71 highlights the urgency of developing preventive and treatment agents. Recent studies have reported the emergence of novel antiviral agents and vaccines that utilize microRNAs (miRNAs). They belong to a class of small (19-24 nt) non coding RNA molecules. As miRNAs play a major role in the host regulatory system, there is a huge opportunity for interplay between host miRNAs and EV-A71 expressions. A total of 42 out of 64 miRNAs were up-regulated in EV-A71-infected cells. There was consistent up-regulation of miR-1246 gene expression that targeted the DLG3 gene which contributes to neurological pathogenesis. In contrast, miR-30a that targets calcium channels for membrane transportation was down-regulated. This leads to repression of EV-A71 replication. The impact of host miRNAs on immune activation, shutdown of host protein synthesis, apoptosis, signal transduction and viral replication are discussed. miRNAs have been used in the construction of live attenuated vaccines (LAV) such as the poliovirus LAV that has miRNA binding sites for let-7a or miR-124a. The miRNAbearing vaccine will not replicate in neuronal cells carrying the corresponding miRNA but could still replicate in the gastrointestinal tract and hence remains to act as immunogens. As such, miRNAs are attractive candidates to be developed as vaccines and antivirals.
Matched MeSH terms: Hand, Foot and Mouth Disease/drug therapy; Hand, Foot and Mouth Disease/prevention & control; Hand, Foot and Mouth Disease/therapy*
Enterovirus 71 (EV71), a causative agent of hand, foot, and mouth disease can be classified into three genotypes and many subtypes. The objectives of this study were to conduct a molecular epidemiological study of EV71 in the central region of Taiwan from 2002-2012 and to test the hypothesis that whether the alternative appearance of different EV71 subtypes in Taiwan is due to transmission from neighboring countries or from re-emergence of pre-existing local strains. We selected 174 EV71 isolates and used reverse transcription-polymerase chain reaction to amplify their VP1 region for DNA sequencing. Phylogenetic analyses were conducted using Neighbor-Joining, Maximum Likelihood and Bayesian methods. We found that the major subtypes of EV71 in Taiwan were B4 for 2002 epidemic, C4 for 2004-2005 epidemic, B5 for 2008-2009 epidemic, C4 for 2010 epidemic and B5 for 2011-2012 epidemic. Phylogenetic analysis demonstrated that the 2002 and 2008 epidemics were associated with EV71 from Malaysia and Singapore; while both 2010 and 2011-2012 epidemics originated from different regions of mainland China including Shanghai, Henan, Xiamen and Gong-Dong. Furthermore, minor strains have been identified in each epidemic and some of them were correlated with the subsequent outbreaks. Therefore, the EV71 infection in Taiwan may originate from pre-existing minor strains or from other regions in Asia including mainland China. In addition, 101 EV71 isolates were selected for the detection of new recombinant strains using the nucleotide sequences spanning the VP1-2A-2B region. No new recombinant strain was found. Analysis of clinical manifestations showed that patients infected with C4 had significantly higher rates of pharyngeal vesicles or ulcers than patients infected with B5. This is the first study demonstrating that different EV 71 genotypes may have different clinical manifestations and the association of EV71 infections between Taiwan and mainland China.
Matched MeSH terms: Hand, Foot and Mouth Disease/diagnosis; Hand, Foot and Mouth Disease/etiology; Hand, Foot and Mouth Disease/epidemiology*
The aim of the present study was to analyze the sequence of the VP1 gene in enterovirus 71 (EV71) isolates and to explore their genetic evolution, so as to provide a scientific basis for the clinical prevention and treatment of hand, foot and mouth disease. The fecal samples of 590 patients with suspected hand, foot and mouth disease treated at Yan'an Hospital (Kunming, China) between January 2015 and December 2016 were collected and EV71 nucleic acid was detected by fluorescence PCR. The viral RNA of EV71-positive samples was extracted, the VP1 gene was amplified by PCR and the products were sequenced. The VP1 gene sequence was analyzed using DNAMAN and MEGA (version 4.0) software and homologous modeling was performed using Pymol software. A total of 50 EV71-positive samples were identified and the detection rate was 8.47% (50/590 cases). All of the 50 EV71 strains were of the C4 subtype. The genetic distance between the strains detected in the present study and EV71 strains detected in Beijing, Anhui and Malaysia was 0.01-0.03, while that between the strains detected in the present study and Australian strains was 2.11. Homologous modeling indicated that the amino acid sequence of the VP1 gene of the detected strains had a H144Y mutation. There was no significant genetic variation in the EV71 strain within the 2-year period. In conclusion, the EV71 strains detected in the present study was similar to that detected in Beijing, Anhui and Malaysia but different to that from Australia. A point mutation was present in the amino acid sequence of the VP1 gene.
During 2005, 764 children were brought to a large children's hospital in Ho Chi Minh City, Vietnam, with a diagnosis of hand, foot, and mouth disease. All enrolled children had specimens (vesicle fluid, stool, throat swab) collected for enterovirus isolation by cell culture. An enterovirus was isolated from 411 (53.8%) of the specimens: 173 (42.1%) isolates were identified as human enterovirus 71 (HEV71) and 214 (52.1%) as coxsackievirus A16. Of the identified HEV71 infections, 51 (29.5%) were complicated by acute neurologic disease and 3 (1.7%) were fatal. HEV71 was isolated throughout the year, with a period of higher prevalence in October-November. Phylogenetic analysis of 23 HEV71 isolates showed that during the first half of 2005, viruses belonging to 3 subgenogroups, C1, C4, and a previously undescribed subgenogroup, C5, cocirculated in southern Vietnam. In the second half of the year, viruses belonging to subgenogroup C5 predominated during a period of higher HEV71 activity.
Matched MeSH terms: Hand, Foot and Mouth Disease/epidemiology*; Hand, Foot and Mouth Disease/transmission; Hand, Foot and Mouth Disease/virology*
Hand, foot and mouth disease (HFMD) is a prevalent contagious childhood disease typically associated with fever, oral lesions and limb exanthema. While HFMD is caused by a plethora of serotypes of viruses under the genus Enterovirus within the Picornaviridae family, Coxsackievirus A16 (CV-A16) and Enterovirus 71 (EV-A71) are considered the main etiological agents. In recent years however, other viruses have also been isolated in considerable numbers from infected individuals in many regions, joining the legion commonly associated with HFMD. The present study investigated the cytokine and chemokine profiles of HFMD patients from Singapore and Malaysia for the first time. Comparative cohort studies of EV-A71-associated HFMD cases revealed that the Malaysia cohort had a distinct profile from the Singapore cohort, and this could be partly attributed by different EV-A71 genotypes. As the isolation of CV-A6, instead of CV-A16, had become prevalent in the Singapore cohort, it was also of particular interest to study the differential cytokine and chemokine profiles. Our data revealed that overlapping as well as unique profiles exist between the two major causative clinical isolates in the Singapore cohort. Having a better understanding of the respective immunological profiles could be useful for more accurate HFMD diagnosis, which is imperative for disease transmission control until multi-valent vaccines and/or broad-spectrum anti-viral drugs become available.
Matched MeSH terms: Hand, Foot and Mouth Disease/pathology*; Hand, Foot and Mouth Disease/virology
Background. Pre-school children are at a higher risk to acquire infectious diseases such as hand, foot and mouth disease due to their immature immune system. Good hand hygiene prevents transmission of infectious diseases. This study aimed to determine the knowledge and practices of hand hygiene among pre-schoolers. Methods. In this prospective, multi-center study, the pre-schools were selected according to the selection criteria. A questionnaire consisting of socio-demographics, knowledge and practices of hand hygiene were administered via face-to-face interview during the pre- and post-intervention period. A total of 435 pre-schoolers aged 5 and 6 years old from 2 pre-schools within Klang Valley, School P (test group) and School C (control group) were involved in this study. The test group was provided with comprehensive hand hygiene education including video on proper handwashing technique during the 2 months intervention period, whereas the control group did not receive any form of intervention. The data were statistically analyzed using descriptive analysis and independent t-test. Results. Majority of pre-schoolers gained knowledge of handwashing from their parents. However, only 63% demonstrated good handwashing technique. Test group were significantly better (P hand hygiene routine score. Conclusion. A comprehensive hand hygiene education program should include proper handwashing facilities, resources, and awareness of the care-givers in instilling and sustaining good hand hygiene behavior.
Enterovirus A71 (EV-A71) has emerged as the most important cause of large outbreaks of severe and sometimes fatal hand, foot and mouth disease (HFMD) across the Asia-Pacific region. EV-A71 outbreaks have been associated with (sub)genogroup switches, sometimes accompanied by recombination events. Understanding EV-A71 population dynamics is therefore essential for understanding this emerging infection, and may provide pivotal information for vaccine development. Despite the public health burden of EV-A71, relatively few EV-A71 complete-genome sequences are available for analysis and from limited geographical localities. The availability of an efficient procedure for whole-genome sequencing would stimulate effort to generate more viral sequence data. Herein, we report for the first time the development of a next-generation sequencing based protocol for whole-genome sequencing of EV-A71 directly from clinical specimens. We were able to sequence viruses of subgenogroup C4 and B5, while RNA from culture materials of diverse EV-A71 subgenogroups belonging to both genogroup B and C was successfully amplified. The nature of intra-host genetic diversity was explored in 22 clinical samples, revealing 107 positions carrying minor variants (ranging from 0 to 15 variants per sample). Our analysis of EV-A71 strains sampled in 2013 showed that they all belonged to subgenogroup B5, representing the first report of this subgenogroup in Vietnam. In conclusion, we have successfully developed a high-throughput next-generation sequencing-based assay for whole-genome sequencing of EV-A71 from clinical samples.
Matched MeSH terms: Hand, Foot and Mouth Disease/virology*
Outbreaks of hand, foot and mouth disease have been documented in Japan since 1963. This disease is primarily caused by the two closely related serotypes of Enterovirus A71 (EV-A71) and Coxsackievirus A16 (CV-A16). Here, we analyse Japanese virologic and syndromic surveillance time-series data from 1982 to 2015. As in some other countries in the Asia Pacific region, EV-A71 in Japan has a 3 year cyclical component, whereas CV-A16 is predominantly annual. We observe empirical signatures of an inhibitory interaction between the serotypes; virologic lines of evidence suggest they may indeed interact immunologically. We fit the time series to mechanistic epidemiological models: as a first-order effect, we find the data consistent with single-serotype susceptible-infected-recovered dynamics. We then extend the modelling to incorporate an inhibitory interaction between serotypes. Our results suggest the existence of a transient cross-protection and possible asymmetry in its strength such that CV-A16 serves as a stronger forcing on EV-A71. Allowing for asymmetry yields accurate out-of-sample predictions and the directionality of this effect is consistent with the virologic literature. Confirmation of these hypothesized interactions would have important implications for understanding enterovirus epidemiology and informing vaccine development. Our results highlight the general implication that even subtle interactions could have qualitative impacts on epidemic dynamics and predictability.
Matched MeSH terms: Hand, Foot and Mouth Disease/epidemiology*; Hand, Foot and Mouth Disease/virology*
Hand, foot and mouth disease (HFMD) is a highly contagious, world-wide distributed viral illness that affects predominantly children. It is caused by several enteroviruses, such as coxsackieviruses A6, A10, A16 and enterovirus 71. In most cases, HFMD follows a benign and self-limiting course. After an incubation period of 3 to 10 days, fever and sore throat, the first symptoms of the disease, appear. A few days later, maculopapular or vesicular eruptions form on the palms and soles as well as in the oral cavity. Since the year 2000, several large HFMD outbreaks have been reported in many Asian regions such as China, Malaysia and Vietnam. In some of these outbreaks, high incidences of severe progressive HFMD forms with some fatalities were observed. Such diseases have been caused primarily by enterovirus 71 strains and were characterized frequently by sudden onset of fever, encephalitis/meningitis and severe respiratory symptoms such as pulmonary edema. Further severe neurological and cardiac complications have also been observed during these outbreaks. Recently, some HFMD outbreaks caused by the coxsackievirus A6 have been reported in several parts of the world. These illnesses also affected adults and were characterized by more severe symptoms of "classical" HFMD. In addition, outbreaks of coxsackievirus-A6-associated HFMD in many countries were associated with onychomadesis, with the loss of nails occurring up to two months after initial symptoms. Treatment of "classical" HFMD is usually symptomatic, a generally recommended antiviral therapy does not exist. In severe HFMD cases, suitable treatment also encompasses mechanical ventilation, as well as the additional application of antiviral agents such as ribavirin. In the last years, several novel agents with good in vitro and in vivo activity against enteroviruses have been developed. A vaccine against HFMD is not yet available.
Matched MeSH terms: Hand, Foot and Mouth Disease/diagnosis; Hand, Foot and Mouth Disease/drug therapy*; Hand, Foot and Mouth Disease/epidemiology; Hand, Foot and Mouth Disease/virology
Enterovirus 71 (EV71) and Coxsackievirus A16 (CVA16) are two viruses commonly responsible for hand, foot and mouth disease (HFMD) in children. The lack of prophylactic or therapeutic measures against HFMD is a major public health concern. Insect cell-based EV71 and CVA16 virus-like particles (VLPs) are promising vaccine candidates against HFMD and are currently under development. In this paper, the influence of insect cell line, incubation temperature, and serial passaging effect and stability of budded virus (BV) stocks on EV71 and CVA16 VLP production was investigated. Enhanced EV71 and CVA16 VLP production was observed in Sf9 cells compared to High Five™ cells. Lowering the incubation temperature from the standard 27°C to 21°C increased the production of both VLPs in Sf9 cells. Serial passaging of CVA16 BV stocks in cell culture had a detrimental effect on the productivity of the structural proteins and the effect was observed with only 5 passages of BV stocks. A 2.7× higher production yield was achieved with EV71 compared to CVA16. High-resolution asymmetric flow field-flow fractionation couple with multi-angle light scattering (AF4-MALS) was used for the first time to characterize EV71 and CVA16 VLPs, displaying an average root mean square radius of 15±1nm and 15.3±5.8 nm respectively. This study highlights the need for different approaches in the design of production process to develop a bivalent EV71 and CVA16 vaccine.
Matched MeSH terms: Hand, Foot and Mouth Disease/immunology; Hand, Foot and Mouth Disease/prevention & control; Hand, Foot and Mouth Disease/virology
Enterovirus 71 (EV71) is a major aetiological agent of hand, foot and mouth disease (HFMD). In recent years, several outbreaks in East Asia were associated with neurological complications and numerous deaths. An outbreak in Singapore in October 2000 afflicted thousands of children, resulting in four fatal cases from three of whom EV71 was isolated. The genomes of two representative EV71 strains isolated from a fatal case and a surviving patient were completely sequenced, and their nucleotide and amino acid sequences compared with known EV71 strains. The two outbreak strains were classified under genogroup B, together with those previously isolated in Singapore, Malaysia and Japan. Comparative sequence analysis of the two Singapore strains revealed 99% nucleotide similarity, while their deduced amino acid sequences were almost identical except for residue 1506 in the 3A non-structural region. Given that the outbreak involved closely related genetic variants of EV71, the broad spectrum of disease severity may be attributed to critical factors such as varying viral inoculation doses or differing host immune responses following infection, but is less likely to be due to the emergence of EV71 strains with heightened virulence.
Matched MeSH terms: Hand, Foot and Mouth Disease/mortality; Hand, Foot and Mouth Disease/epidemiology*; Hand, Foot and Mouth Disease/virology
A specific and sensitive method based on RT-PCR was developed to detect enterovirus 71 (EV71) from patients with hand, foot and mouth disease, myocarditis, aseptic meningitis and acute flaccid paralysis. RT-PCR primers from conserved parts of the VP1 capsid gene were designed on the basis of good correlation with sequences of EV71 strains. These primers successfully amplified 44 strains of EV71 including 34 strains isolated from Singapore in 1997 and 1998, eight strains from Malaysia isolated in 1997 and 1998, one Japanese strain and the neurovirulent strain EV71/7423/MS/87. RT-PCR of 30 strains of other enteroviruses including coxsackievirus A and B, and echoviruses failed to give any positive amplicons. Hence, RT-PCR with these primers showed 100% correlation with serotyping. Direct sequencing of the RT-PCR products of 20 EV71 strains revealed a distinct cluster with two major subgroups, thus enabling genetic typing of the viruses. The genetic heterogeneity of these strains culminated in amino acid substitutions within the VP1, VP2 and VP3 regions. The sequencing of a 2.9 kb fragment comprising the capsid region and the major part of 5' UTR of two Singapore strains revealed that they belonged to a group distinct from the prototype EV71/BrCr strain and the EV71/7423/MS/87 strain. The dendrogram generated from 341 bp fragments within the VP1 region revealed that the strains of Singapore, Malaysia and Taiwan belong to two entirely different EV71 genogroups, distinct from the three genogroups identified in another recent study.
Matched MeSH terms: Hand, Foot and Mouth Disease/virology*
Recently, there have been large outbreaks of hand, foot and mouth disease (HFMD) mainly caused by enterovirus 71 (EV71) associated with severe neurological diseases in the Western Pacific Region (WPR). To monitor the realtime trend of EV71 transmission throughout the WPR, the authors conducted a molecular epidemiological analysis of EV71 infection.
Matched MeSH terms: Hand, Foot and Mouth Disease/epidemiology*; Hand, Foot and Mouth Disease/virology
Enterovirus 71 (EV71), one of the major causative agents for hand, foot and mouth disease (HFMD), is sometimes associated with severe central nervous system diseases. In 1997, in Malaysia and Japan, and in 1998 in Taiwan, there were HFMD epidemics involving sudden deaths among young children, and EV71 was isolated from the HFMD patients, including the fatal cases. The nucleotide sequences of each EV71 isolate were determined and compared by phylogenetical analysis. EV71 strains from previously reported epidemics belonged to genotype A-1, while those from recent epidemics could be divided into two genotypes, A-2 and B. In Malaysia, genotype A-2 was more prevalent, while in Japan and Taiwan, B genotype was more prevalent. Two isolates from fatal cases in Malaysia and one isolate from a fatal case in Japan were genotype A-2. However, all isolates from three fatal cases in Taiwan belonged to genotype B. The severity of the HFMD did not link directly to certain genotypes of EV71.
Matched MeSH terms: Hand, Foot and Mouth Disease/epidemiology*; Hand, Foot and Mouth Disease/virology*
From July through December 1997, 11 previously healthy children in Peninsular Malaysia succumbed to an illness clinically characterised by an acute severe refractory left-ventricular failure, following a brief prodromal illness, in the midst of an outbreak of hand, foot and mouth disease (HFMD), similar to the reported experience in Sarawak and Taiwan. Retrospective reviews of the clinical features and results of laboratory, pathological and virological investigations of cases were conducted. The median age of the 11 case-patients was 31 months (range, 13 to 49 months); 6 were males. A brief prodromal illness of 3 days (range, 2 to 5 days) was characterised by fever (axillary temperature > 38 degrees C) (100%), oral ulcers (72%), extremity rashes (45%) and significant vomiting (55%). Upon hospitalisation, 7 of 11 case-patients had features suggestive of cardiogenic shock, while 4 of 11 case-patients developed shock during hospitalisation as evidenced by marked sustained tachycardia (heart rate > or = 180 beats per minute), poor peripheral pulses and peripheral perfusion, mottled extremities, pulmonary oedema (haemorrhagic pulmonary secretions in 8 of 11 cases during tracheal intubation, often precipitated by conservative crystalloid boluses, and radiographic evidence of acute pulmonary oedema in 5 of 7 cases) and markedly impaired left ventricular function on echocardiographic examination (7 of 7 cases). Three of 4 case-patients had aseptic meningitis while one case-patient also had an acute flaccid paraparesis. Despite supportive therapy, death occurred within a median of 13.4 hours following hospitalization. Post-mortem findings (all 8 specimens examined) consistently demonstrated brain-stem encephalitis with foci of neuronal necrosis and micro-abscesses. None of the 11 specimens examined revealed histological evidence of myocarditis. Enterovirus 71 (EV71) was detected in 10 of 11 case-patients, many (7) from various sterile tissue sites (5 from central nervous tissues). No other viruses were isolated or identified. Clinical features and pathological studies closely paralleled the reported experience in Sarawak and Taiwan. The uniform necropsy findings of necrotizing brain-stem encephalitis coupled with essentially normal myocardial histology, in concert with the concurrent and consistent detection of EV71 points to a primary EV71 encephalitis; as yet unclear neurogenic mechanisms may account for the cardiovascular manifestations.
Matched MeSH terms: Hand, Foot and Mouth Disease/mortality*; Hand, Foot and Mouth Disease/pathology*
Hand, foot and mouth disease (HFMD) is endemic in Sarawak, Malaysia. In this study, a geographical information system (GIS) was used to investigate the relationship between the reported HFMD cases and the spatial patterns in 11 districts of Sarawak from 2006 to 2012. Within this 7-years period, the highest number of reported HFMD cases occurred in 2006, followed by 2012, 2008, 2009, 2007, 2010 and 2011, in descending order. However, while there was no significant distribution pattern or clustering in the first part of the study period (2006 to 2011) based on Moran's I statistic, spatial autocorrelation (P = 0.068) was observed in 2012.
Matched MeSH terms: Hand, Foot and Mouth Disease/epidemiology*
Hand, Foot and Mouth Disease (HFMD) is caused by multiple Enterovirus (EV) serotypes mainly coxsackievirus A6 (CV-A6), coxsackievirus A16 (CV-A16) and Enterovirus 71 (EV-A71). Recurrent HFMD infections are rarely reported. An unusual rise in HFMD cases was reported in Mumbai during May-June 2018. Stool and throat swab specimens were referred from seven children from two hospitals for laboratory diagnosis. The age group of cases ranged from 9 months to 5 years with median age 13 months. Out of seven cases, three were males and four females. One 13-month-old female case was reported twice within 21 days. Stool, throat swab specimens were tested by pan enterovirus RT-PCR and also by virus isolation using human rhabdomyosarcoma cell line for detection of Enteroviruses. Out of seven HFMD cases, CV-A6 and CV-A16 viruses were isolated from five and two cases respectively. The phylogenetic analysis of CV-A6 viruses showed their similarity with CV-A6 viruses from Finland and China, whereas the two CV-A16 isolates showed similarity with those from Japan, France, China, Sarawak and Thailand. For the recurrent HFMD case, CV-A6 and CV-A16 were isolated from the stool specimens collected during the first and second episodes, respectively. There are no reports of isolation and molecular characterization of CV-A6 and CV-A16 viruses from recurrent HFMD cases. The present study reports molecular characterization of two Enterovirus serotypes CV-A6 and CV-A16 from a recurrent HFMD case, highlighting need of virological and molecular surveillance of HFMD.