OBJECTIVEThis report presented an overview on the epidemiology of enterovirus in Yunnan province, the People's Republic of China.

METHODSA total of 210 strains of non-polioviruses isolated under acute flaccid paralysis surveillance during a 5-year study period from 1997 to 2000 and 2004 were examined. Of the 210 non-polioviruses strains, a total of 12 strains of adenoviruses were serologically identified. The remaining 198 isolates were used for molecular typing, and the viral genomes of 195 nonpolio enteroviruses (NPEVs) were translated to corresponding amino acid sequences and compared with those of the prototype strains.

RESULTSBased on molecular typing, 5 isolates were classified into 5 serotypes of human enterovirus A species while 158 isolates into 34 serotypes of B and 32 isolates into 6 serotypes of C species. However, we did not isolate any viruses which belonged to human enterovirus D species. Thus, under acute flaccid paralysis surveillance, human enterovirus B species accounted for 75.2% of the 210 isolates and was considered as the predominant one, followed by human enterovirus C (12.2%), adenovirus (5.7%), and human enterovirus A (2.4%).

CONCLUSIONAlthough the epidemiological characteristics of NPEVs from Yunnan province remained "unknown", the molecular typing method had provided us a breakthrough to understand the epidemiology of these viruses.

China ; epidemiology ; Enterovirus ; classification ; genetics ; isolation & purification ; Enterovirus Infections ; epidemiology ; Genes, Viral ; Humans ; Molecular Epidemiology ; Serotyping

China ; epidemiology ; Enterovirus A, Human ; genetics ; isolation & purification ; Enterovirus Infections ; diagnosis ; drug therapy ; epidemiology ; etiology ; Humans

Capsid Proteins ; genetics ; isolation & purification ; Child ; Cloning, Organism ; Enterovirus ; genetics ; isolation & purification ; Enterovirus Infections ; virology ; Gene Expression ; Humans

We analyzed the genetic characteristics of coxsackievirus A4 (CV-A4) based on the entire VP1 coding region. Samples were isolated from patients with acute flaccid paralysis (AFP) in Shaanxi, China from 2006 to 2010. We wished to ascertain the predominant genotype and the relationship between CV-A4 infection and AFP. Sixty-eight non-polio enteroviruses were inoculated onto RD cells (to increase the virus titer) and molecular typing was undertaken. The entire VP1 coding region was amplified. Percentage of CV-A4 was 10.3% (7/68). Analyses of genetic identify and creation of phylogenetic trees revealed that CV-A4 could be classified into A, B and C genotypes. Seven CV-A4 strains from Shaanxi and other CV-A4 strains from China formed an independent evolution lineage located in group 4 and belonged to the C2 sub-genotype. These data suggested that CV-A4 strains of sub-genotype C2 were the predominant genotypes in China. These strains co-evolved and co-circulated with those from other provinces in China, so continued monitoring of CV-A4 (by clinical and genetic surveillance) should be enhanced.
China ; Enterovirus A, Human ; classification ; genetics ; isolation & purification ; Enterovirus Infections ; virology ; Genotype ; Humans ; Paralysis ; virology ; Phylogeny ; Viral Proteins ; genetics

To study on the phylogenetic characterization of the VP1 genes of coxsackievirus A16 (CVA16) causing hand-food-mouth disease (HFMD) isolated from Anhui province in 2014. A total of 413 throat swab specimens from HFMD patients were collected during January to November, 2014 for the isolation and identification of enteroviruses using real-time RT-PCR assays. The VP1 regions of CVA16 isolates were amplified using RT-PCR and sequenced. And the phylogenetic tree was constructed among the VP1 regions of those isolates, the different genotypes and sub-genotypes of CVA16 strains. A total of 97 enteroviruses were isolated from 413 samples, the positive rate was 23.49% (97/413), including seventeen CVA16, seventy six HEV71 and four other enteroviruses. The results of the phylogenetic tree showed that 17.CVA16 strains isolated from Anhui in 2014 clustered within B1b evolution branch of B1 genotype. The nucleotide and amino acid sequence identities were 95.30%-100% and 98.70%-100% among the isolates, respectively, but within B1b branch of 17 strains formed several small transmission chains. The nucleotide acid of 17 CVA16 isolates in Anhui province were closed to the strains isolated from Yunnan, Hunan, Guangdong, Tibet and Jiangsu, especially from Hunan in 2013 and from Shenzhen of Guangdong in 2014, the identity were 96.40%-99.70%. The CVA16 strains isolated from Anhui in 2014 were all belong to genetic subtype B1b of B1 genotype was dominant, and among those isolates, several small virus transmission chains had formed with co-circulating and evolution.
China ; Enterovirus A, Human ; classification ; genetics ; isolation & purification ; Enterovirus Infections ; virology ; Genotype ; Humans ; Molecular Sequence Data ; Phylogeny ; Viral Proteins ; genetics ; metabolism

More and more new human enteroviruses (HEVs) types were identified with the broad application of the molecular serotyping methods for enteroviruses. Since enterovirus 71 (EV71) was first reported in 1969, numerous epidemic outbreaks associated with new enteroviruses have occurred all around the world, and pose a significant threat to public health . The epidemics of hand, foot and mouth disease (HFMD) caused by EV71 infection in China have raised great concern of global scholars. This paper reviewed research progress in recent years of the molecular typing, evolution, epidemiology, and pathogenesis attributable to new enterovirus types.
Animals ; Enterovirus ; classification ; genetics ; isolation & purification ; Enterovirus Infections ; veterinary ; virology ; Haplorhini ; Humans ; Pan troglodytes ; Phylogeny ; Primate Diseases ; virology

In order to explore the genotype distribution and molecular evolution of non-polio enterovirus (NPEVs)in Yunnan Province,the People's Republic of China, we sequenced and analyzed the partial VP1 coding region of 105 NPEVs isolated from acute flaccid paralysis (AFP) surveillance in Yunnan province during a 5- year study period from 2006 to 2010. The viral genomes of 105 NPEVs were translated to corresponding amino acid sequences and compared with those of the prototype strains, and the phylogenetic tree was constructed among these VP1 nucleotide sequences and other prototype strains from GenBank. Analysis showed that 18 isolates were classified into 7 serotypes of human enterovirus A species, while 77 isolates into 22 serotypes of B and 10 isolates into 4 serotypes of C species. However, we did not isolate any viruses which belonged to human enterovirus D species. Thus, under AFP surveillance, human enterovirus B species accounted for 73. 3% of the 105 isolates and was considered as the predominant one,followed by human enterovirus A(17. 1%) and human enterovirus C(9. 5%). Phylogenetic analysis showed that various serotypes of the virus and the corresponding prototype strains or other representative strains clustered into the same grooup, however, Yunnan strains and prototype strains were located in the different branches (except CA2,EV90 and EV76). The degree of variation was different even among the same genotype strains. This report showed that different genotype strains spread widely in Yunnan Province.
China ; epidemiology ; Enterovirus ; classification ; genetics ; isolation & purification ; Enterovirus Infections ; epidemiology ; virology ; Humans ; Molecular Sequence Data ; Molecular Typing ; Phylogeny

This report presents an overview of human enterovirus B species in Henan Province. A total of 14 isolates of HEV-B species isolated under HFMD surveillance network during the six months in 2010 were examined. Based on molecular typing results targeting VP1 region, 14 isolates were classified into 6 serotypes of HEV-B. Furthermore, comparison of these 14 isolates with reference strains and strains in mainland China was conducted. The phylogenetic analysis revealed that E25, E11 and E6 showed homology with those from Shandong Province which adjoins Henan Province. E1 and E13 showed homology with those from Yunnan Province, and E30 showed homology with Henan strain isolated in 2008. Cocirculation of two lineages of echovirus 6 was observed.
China ; epidemiology ; Enterovirus B, Human ; classification ; genetics ; isolation & purification ; Enterovirus Infections ; epidemiology ; virology ; Feces ; virology ; Humans ; Molecular Sequence Data ; Phylogeny

This research firstly reported the molecular analysis of ECHO25 (Entric Cytopathic Human Orphanviruses Type 25). To clarify molecular characteristics of the ECHO25 virus isolates in Henan Province and its relationship with the rest of world's isolates,the complete VP1 sequences of the 4 isolates in Henan were successfully amplified by RT-PCR and were compared with other ECHO25 isolates available from GenBank. Compared with the prototype strain JV-4, the nucleotide sequence identity was 79.2%-80.1%, and the amino sequence identity was 89.0%-92.4, the nucleotide sequence identity among the 4 strains isolates in Henan Province was 93.0%-99.0%, the amino sequence identity was 92.4%-97.5%. HN-01 and HN-26 strains had the highest level of homology, the nucleotide homology was 99.0%; All the 4 strains belonged to the B1 genotype.
China ; epidemiology ; Enterovirus B, Human ; classification ; genetics ; isolation & purification ; Enterovirus Infections ; epidemiology ; virology ; Humans ; Molecular Sequence Data ; Phylogeny

To reveal the genetic features and recombination of enterovirus 71 isolates between 2008 and 2010. A total of 5 enterovirus 71 isolates were sequenced completely and phylogenetic analysis and recombination were performed. Phylogenetic analysis based on VP1 regions revealed that the Henan enterovirus 71 between 2008 and 2010 belonged to C4a in subgenotype C4. Bootscan analyses and phylogenetic analysis based on the 5'UTR, P1, P2, P3 genomic regions revealed the recombinations between EV71 genotypes B and C at the 2A-2B junction, and between EV71 genotype B and CA16 strain G-10 at the 3B-3C junction. Henan enterovirus 71 isolates between 2008 and 2010 belonged to C4a in subgenotype C4 which was the predominant virus genotype circulating in mainland China since 2004, a combination of intratypic and intertypic recombination were found in EV71 subgenotype C4.
Capsid Proteins ; genetics ; Child ; Child, Preschool ; China ; epidemiology ; Enterovirus ; classification ; genetics ; isolation & purification ; Enterovirus Infections ; epidemiology ; virology ; Feces ; virology ; Genome, Viral ; genetics ; Genotype ; Humans ; Infant ; Phylogeny ; Recombination, Genetic