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Metagenomic analysis of mosquito-borne and mosquito-specific viruses is useful to understand the viral diversity and for the surveillance of pathogens of medical and veterinary importance. Yunnan province is located at the southwest of China and has rich abundance of mosquitoes. Arbovirus surveillance is not conducted regularly in this province particularly at animal farms, which have public health as well as veterinary importance. Here, we have analyzed 10 pools of mosquitoes belonging to Culex tritaeniorhyncus, Aedes aegypti, Anopheles sinensis, and Armigeres subalbatus species, collected from different animal farms located at Yunnan province of China by using metagenomic next-generation sequencing technique. The generated viral metagenomic data reveal that the viral community matched by the reads was highly diverse and varied in abundance among animal farms, which contained more than 19 viral taxonomic families, specific to vertebrates, invertebrates, fungi, plants, protozoa, and bacteria. Additionally, a large number of viral reads were related to viruses that are non-classified. The viral reads related to animal viruses included parvoviruses, anelloviruses, circoviruses, flaviviruses, rhabdoviruses, and seadornaviruses, which might be taken by mosquitoes from viremic animal hosts during blood feeding. Notably, the presence of viral reads matched with Japanese encephalitis virus, Getah virus, and porcine parvoviruses in mosquitoes collected from different geographic sites suggested a potential circulation of these viruses in their vertebrate hosts. Overall, this study provides a comprehensive knowledge of diverse viral populations present at animal farms of Yunnan province of China, which might be a potential source of diseases for humans and domestic animals. [ABSTRACT FROM AUTHOR]

The study represents the genetic overview of non-polio enteroviruses (NPEV) isolated from acute flaccid paralysis (AFP) cases in Yunnan Province from 2006 to 2010. Molecular typing based on VP1 nucleotide sequence was carried out on 98 NPEV isolates, and 33 serotypes were identified. EV-B was detected most frequently with an overall prevalence of 71.4%, followed by EV-A (18.4%) and EV-C (10.2%). No EV-D was identified. NPEV positive rate was higher in children <3 years of age and in summer and autumn months. Clinically, 68.4% patients presented with fever, and 16 cases (16.3%) were classified as Guillain-Barré syndrome, followed by myositis (13.3%). The phylogenetic analysis on the VP1 and 3D regions of prevalent serotypes provided evidence for recombination events among them. EV-A71, an important pathogen previously demonstrated to be associated with paralysis, had also been detected (n=8) in this study and they all belonged to genotype C4. Great genetic divergence between Yunnan isolates and strains from other regions of the world was revealed. The findings of the study are of great importance for further research on molecular evolution of EV under the circumstance of no specialized EV surveillance system in China. [ABSTRACT FROM AUTHOR]

Human enterovirus B106 (EV-B106) is a recently identified member of enterovirus species B. In this study, we report the complete genomic characterization of an EV-B106 strain (148/YN/CHN/12) isolated from an acute flaccid paralysis patient in Yunnan Province, China. The new strain had 79.2-81.3% nucleotide and 89.1-94.8% amino acid similarity in the VP1 region with the other two EV-B106 strains from Bolivia and Pakistan. When compared with other EV serotypes, it had the highest (73.3%) VP1 nucleotide similarity with the EV-B77 prototype strain CF496-99. However, when aligned with all EV-B106 and EV-B77 sequences available from the GenBank database, two major frame shifts were observed in the VP1 coding region, which resulted in substantial (20.5%) VP1 amino acid divergence between the two serotypes. Phylogenetic analysis and similarity plot analysis revealed multiple recombination events in the genome of this strain. This is the first report of the complete genome of EV-B106. [ABSTRACT FROM AUTHOR]