Most isolates of foot-and-mouth disease virus (FMDV) display a broad host range. Since the late 1990s, the genetic lineage of PanAsia topotype FMDV serotype O has caused epidemics in the Far East, Africa, the United Kingdom, France, the Netherlands, and numerous other countries throughout Europe and Asia. In contrast, there are several FMDV isolates that exhibit a more restricted host range. A Cathay topotype isolate of FMDV serotype O from the 1997 epizootic in Taiwan (O/TAW/97) demonstrated restricted host specificity, only infecting swine. Methods used to evaluate infectivity and pathogenicity of FMDV isolates in cattle are well-documented, but there has been less progress studying transmission and pathogenicity of FMDV isolates in pigs. In previous studies designed to examine pathogenicity, various chimeric viruses derived from O/TAW/97 were intradermally inoculated in the heel bulb of pigs. Subsequent quantitative scoring of disease and evaluation of virus released into nasal secretions and blood was assessed. Here we prove the usefulness of this method in direct and contact inoculated pigs to evaluate infectivity, pathogenicity and transmission of different Asian FMDV isolates. Virus strains within the Cathay topotype were highly virulent in swine producing a synchronous disease in inoculated animals and were efficiently spread to in-contact naive pigs, while virus strains from the PanAsia topotype displayed more heterogeneous properties.
Animals ; Antibodies, Viral/blood ; Disease Outbreaks/*veterinary ; Foot-and-Mouth Disease/epidemiology/transmission/*virology ; Foot-and-Mouth Disease Virus/*pathogenicity ; Host Specificity ; Swine ; Swine Diseases/epidemiology/transmission/*virology ; Taiwan/epidemiology

China ; epidemiology ; Enterovirus ; genetics ; isolation & purification ; Genes, Viral ; Hand, Foot and Mouth Disease ; epidemiology ; virology ; Humans

China ; epidemiology ; Enterovirus A, Human ; genetics ; isolation & purification ; Hand, Foot and Mouth Disease ; epidemiology ; virology ; Humans ; Molecular Epidemiology ; Phylogeny

Hand, foot, and mouth disease (HFMD) is a viral infectious disease regarded to be a public-health problem worldwide. Since the 1990s, HFMD began to spread in the Asia-Pacific region (especially in South-East Asia). HFMD outbreaks have occurred in mainland China frequently since 2008, and the morbidity and mortality of HFMD has continued to increase in recent years. In mainland China, enterovirus A serotype enterovirus A71 (EV-A71) and coxsackievirus A16 (CVA16) have been the major pathogens of HFMD during these years. However, the etiological spectrum of HFMD changes with time. This review focuses mainly on the etiological spectrum of HFMD and changes in epidemic patterns in mainland China.
China ; epidemiology ; Disease Outbreaks ; Enterovirus ; classification ; genetics ; isolation & purification ; Hand, Foot and Mouth Disease ; epidemiology ; virology ; Humans ; Prevalence

OBJECTIVETo analyze the etiological and epidemiological characteristics of hand-foot-and-mouth disease (HFMD) seen in Jiangsu province from 2008 to 2010, and provide evidence for its prevention and control.

METHODSBased on the requirement of supervision program of HFMD, surveillance and report were done according to National Disease Supervision Information Management System. Descriptive epidemiological method, performed between 2008 and 2010, was used to analyze the time, region and population distribution and results of etiologic analysis of HFMD. Nucleic acid of enterovirus (EV) genome was detected by real-time RT-PCR.

RESULTSThe average incidence rate of HFMD was 86.70 per million between 2008 and 2010, the peak incidence occurred in April to July. There were significant differences among the incidence in different districts (P<0.05), and the highest incidence was seen in the densely inhabited southern areas of Jiangsu province. Most of the cases were infants and children aged less than 5 years. The number of male cases (2008: 17,008, 2009: 48 768, 2010: 50,231) was much larger than that of the female cases 2008: 9662, 2009: 29 151, 2010: 30,655. The HFMD cases with mild symptoms were caused mainly by enterovirus 71 (EV71) and coxsackievirus A16 (Cox A16) and there was difference among different years. The severe HFMD cases and deaths were mainly caused by EV71 infection.

CONCLUSIONSThe epidemiologic characteristics of HFMD in Jiangsu province from 2008 to 2010 had close relationship with season, population and region. The mild cases of HFMD were mainly infected with EV71 and Cox A16. However, EV71 illness seemed to be more severe and had significantly greater frequency of serious complications and fatality than the illness caused by Cox A16.

Child, Preschool ; China ; epidemiology ; Disease Outbreaks ; Enterovirus A, Human ; pathogenicity ; Female ; Hand, Foot and Mouth Disease ; epidemiology ; virology ; Humans ; Infant ; Male

OBJECTIVETo explore the clinical and epidemiological characteristics of serious cases of hand-foot-and-mouth disease (HFMD) infected by EV71, in order to provide scientific evidence for prevention and control of HFMD.

METHODSInformation was collected by questionaires through consulting medical cases. Data was input by Epidata, and analysed by software SAS 9.13.

RESULT201 severe cases were investigated. 84.65% of the cases were below 3 years old. The youngest one was 5 months and the oldest one was 8 years old. The ratio for male and female was 2.2: 1.85. 08% of the cases were distributed sporadically. 51.74% of them lived in rural, 29.36% of them lived in urban and 19.9% of them lived at the fringe area of rural and urban. 81.59% of the cases became serious between 1 and 4 days after infected. 100% cases had fever and 99.95% of them had a rash. 96.52% of them had nerve system symptoms. The main complications were virulent spinal encephalitis, pneumonia and breathing exhaustion. 98.01% of the patients were recovered or cured.

CONCLUSIONThe cases aged below 3 years old are high risk persons. Rural area and the fringe area of rural and urban are the key area for disease control. 1-4 days after onset is the key period to prevent complications.

Child ; Child, Preschool ; China ; epidemiology ; Enterovirus A, Human ; isolation & purification ; Female ; Hand, Foot and Mouth Disease ; epidemiology ; pathology ; virology ; Humans ; Infant ; Male

Central Nervous System Diseases ; complications ; virology ; Child ; China ; epidemiology ; Enterovirus ; Enterovirus A, Human ; Female ; Hand, Foot and Mouth Disease ; complications ; epidemiology ; Humans

An etiology study on HFMD in Qingdao region during 2008-2009 was conducted. The virus RNA were isolated from throat swabs of HFMD,the EV, EV71 and CVA16 were detected by multiplex realtime RT-PCR. For those specimens with EV positive and both EV71 and CVA16 negative,a reverese transcription-seminested polymerase chain reaction (RT-snPCR) was perfomed to amplify part sequence of the VP1 gene for sabsequent analysis to identify the serotype. The results indicated that EV71 and CVA16 were the major pathogens of HFMD in Qingdao during 2008-2009. The proportion of EV71 was greater than CVA16 in either mild or serious HFMD cases. Sequence analysis showed that 5 non-EV71 and non-CVA16 serotypes (8 specimens) were obtained in 2008 including Coxsackievirus A5, A6, A10, A12 and Echovirus 9, which were well distributed. Three serotypes(13 specimens) were obtained in 2009 including Coxsackievirus A9, A12 and B2, of which CVA12 was of a big proportion (11/13). CVA12 became a new relatively major pathogen of HFMD in Qingdao during 2009.
China ; epidemiology ; Enterovirus ; classification ; genetics ; isolation & purification ; Hand, Foot and Mouth Disease ; epidemiology ; virology ; Humans ; Phylogeny ; RNA, Viral ; genetics ; Serotyping

Child ; Child, Preschool ; China ; epidemiology ; Enterovirus A, Human ; Female ; Hand, Foot and Mouth Disease ; epidemiology ; virology ; Humans ; Infant ; Infant, Newborn ; Male

OBJECTIVETo analyze the genetic evolution for the common causative agent of hand, foot and mouth disease(HFMD) that VP4 of human enterovirus 71 in Shenzhen district.

METHOD491 sttol specimen were collected from, children with hand, foot and mouth diease in Shenzhen Children's Hospital 2009. After cell culture, VP4 gene of eight EV71 strains were amplified by reverse-transcriptase PCR( RT-PCR), phylogenetic analysis of the VP4 gene was constructed by using MEGA 4. 0.

RESULTThe VP4 gene of eight EV71 strains encoding 69 amino acids with full length 207 bp. The nucleotide homology of VP4 gene among eight EV71 strains was 94. 2% -98. 1%, compared with VP4 gene of EV71 strains retrieved from Shenzhen 2001 to 2004 and GenBank was 89. 1%-98. 1% and 79.2%-100% respectively. Asian epidemic strain Fuyang had the highest nucleotide homology, representative strain C4 and Shenzhen strain (AY895144) with 94. 2% -98. 1% secondly. Except for the 54th amino acid of VP4 gene of India reported strain and one of the eight EV71 strains, the homology of the rest amino acids between the eight EV71 strains and those in GenBank was 100%. Compared with representative strain C4,there were seventeen differences in nucleotide sequences of VP4 of the eight EV71 strains. All of the different nucleotides were located at the degenerate password sites except one. There was no significant difference in VP4 gene between the severe and the mild cases of strainS. The eight Shenzhen EV71 strains were classified as sub-genotype C4 in the phylogenetic tree.

CONCLUSIONSThe epidemic of EV71 in Shenzhen 2009 was sub-genotype C4. VP4 gene of EV71 was very conservative which dose not belong to the variation section. The variation of most of nucleotide was invalid variation. The amino acids encoded by VP4 gene which variation was almost zero.

Capsid Proteins ; genetics ; China ; epidemiology ; Enterovirus A, Human ; genetics ; Epidemics ; Evolution, Molecular ; Hand, Foot and Mouth Disease ; epidemiology ; virology ; Humans ; Phylogeny