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To gain more insights into the epidemiology of hantaviruses in the Guizhou province, China, rodents were captured in Guizhou during the period from 2001 to 2003. In addition, serum sample was collected from one patient. Virus isolation was attempted from human serum and rodent samples. Four hantaviruses were isolated successfully in cell culture from one human, two A. agrarius, and one R. norvegicus. The nucleotide sequences for the entire S and M and partial L segment were determined from these four isolates as well as six viruses isolated in 1980s. Phylogenetic analysis revealed that the S segment from all isolates belong to the Hantaan virus (HTNV) clade, regardless of the sources from which they were derived. According to the S sequences, these viruses could be divided into three distinct phylogroups, showing geographical clustering. Analysis of the entire M and the partial L segment sequences demonstrated that 8 out of the 10 isolates belong to the HTNV clade. However, two isolates (CGRn8316 and CGRn9415) isolated from R. norvegicus belong to the Seoul virus (SEOV) clade. In addition, these two isolates were distinct from other known members of SEOV clade. Together, the data suggest that at least three groups of HTNV are co-circulating and one new variant of SEOV may be present in Guizhou. Our results also suggest that HTNV from A. agrarius spilled over to R. norvegicus and natural reassortment between HTNV and SEOV occurred during or after the spillover.

By using multilocus sequence analysis, five Borrelia valaisiana-related strains isolated from rodents and ticks in southwestern China were eventually classified as a new genospecies of B. burgdorferi sensu lato rather than B. valaisiana. The finding explained the differences in transmission cycle and phenotype between B. valaisiana strains from Europe and B. valaisiana-related strains from eastern Asia.Strains of Borrelia burgdorferi sensu lato, the causative agent of Lyme borreliosis, have been divided into at least 13 genospecies (7,8,10,15). The bacterium is maintained mainly in natural foci through the transmission cycles of Ixodes ticks and a wide variety of vertebrate hosts (15). Different B. burgdorferi sensu lato genospecies are distributed unevenly throughout the world and are associated with distinct ecologic features (15).To date, five established genospecies and a group of B. valaisiana-related strains have been isolated in mainland China (7,14,16). B. garinii and B. afzelii are major genospecies in natural foci of northern China and are maintained mainly in a tick-rodent cycle (16). Some B. valaisiana-related strains and B. sinica strains were recently isolated in some regions of the Yangtze River valley (7,14). B. valaisiana-related strains were once tentatively classified as B. afzelii based on the phylogenetic analysis of the rrs gene (2) and then considered to be B. valaisiana based on the phylogenetic analysis of the rrf-rrl intergenic spacer, the rrs gene, and the flagellin gene (4). Recently, Masuzawa et al. suggested that these isolates should be classified as a new genospecies based on a similar phylogenetic analysis (5). In order to clarify the exact taxonomy of B. valaisiana-related strains and explain the differences in transmission cycle and phenotype between B. valaisiana-related strains and B. valaisiana strains, we examined five B. valaisiana-related strains isolated from Guizhou Province in southwestern China by multilocus sequence analysis (MLSA), which was confirmed to surpass the discrimination power of whole-genome DNA-DNA hybridization (the "gold standard" in taxonomy) for B. burgdorferi sensu lato genospecies definition (8, 10). Moreover, new species B. spielmanii and B. californiensis were also confirmed and validated by MLSA (8, 10).Borrelia strains and culture conditions. The five strains used in this study were isolated either from ticks or from the urinary bladders of rodents in Guizhou Province in southwestern China in May 2006, as described previously (1). Strain QTMP2 was from Ixodes granulatus fed from Niviventer fulvescens, strains QSYSP3 and QSYSP4 were from Haemaphysalis longicornis fed from Apodemus agrarius, strain QSDS4 was from A. agrarius, and strain QLZSP1 was from I. granulatus fed from A. agrarius. These strains belong to the B. valaisiana-related group rather than the B. sinica and other B. burgdorferi sensu lato genospecies according to the results of restriction fragment length polymorphism analysis and the analysis of rrf-rrl intergenic spacer sequences...

Since its initial identification in ticks in 2010, Jingmen tick virus (JMTV) has been described in cattle, rodents and primates. To better understand the diversity, evolution and transmission of JMTV, we sampled 215 ticks, 104 cattle bloods, 216 bats and 119 rodents in Wenzhou city, Zhejiang province, China, as well as 240 bats from Guizhou and Henan provinces. JMTV was identified in 107 ticks (from two species), 54 bats (11 species), eight rodents (three species), and 10 cattle, with prevalence levels of 49.8%, 11.8%, 6.7% and 9.6%, respectively, suggesting that bats may be a natural reservoir of JMTV. Phylogenetic analyses revealed that all the newly identified JMTVs were closely related to each other and to previously described viruses. Additionally, all tick and mammalian JMTV sampled in Wenzhou shared a consistent genomic structure, suggesting that the virus can co-circulate between ticks and mammals without observable variation in genome organization. All JMTVs sampled globally could be divided into two phylogenetic groups, Mantel tests suggested that geographic isolation, rather than host species, may be the main driver of JMTV diversity. However, the exact geographical origin of JMTV was difficult to determine, suggesting that this virus has a complex evolutionary history.

During an investigation of arboviruses in China, a novel densovirus (DNV) was isolated from the adult female Culex pipiens pallens. The virus, designated Culex pipiens pallens densovirus (CppDNV), caused cytopathic effect in C6/36 cells. The virus particles were icosahedral, non-enveloped and had a mean diameter of 24 nm. The complete coding region of CppDNV was found to be 3335 nt and it contained three open reading frames (ORFs). CppDNV shares 82-93 % identical nucleotides with isolates of the Aedes albopictus densovirus [isolates AalDNV-1, AalDNV-2 (C6/36 DNV) and , Aedes aegypti densovirus (AaeDNV) and Haemagogus equines densovirus (HeDNV). The nucleotide sequence identity among CppDNV isolates exceeds 98 %. Phylogenetic trees based on non-structural (NS1 and NS2) and capsid (VP) genes show that CppDNV clustered with the species AaeDNV and represents a novel variant of this species within the genus Brevidensovirus.Densoviruses (DNVs) are classified as members of the genera Densovirus, Iteravirus, Brevidensovirus and Pefudensovirus (subfamily Densovirinae) within the family Parvoviridae. They represent a group of non-enveloped viruses, with single-stranded DNA genomes, encapsidated within icosahedrally arranged viral particles. Their host range is limited to a few closely related invertebrates, particularly insects. However, some DNVs also infect and multiply in shrimps. Members of the genera Densovirus and Iteravirus infect lepidopterans (Tijssen & Arella., 1991). Members of the genus Brevidensovirus infect mosquitoes (Ward et al., 2001), while members of the genus Pefudensovirus infect cockroaches. Members of the genera Densovirus and Pefudensovirus have ambisense genomes that are 5.5-6 kb long. Their structural and non-structural proteins are encoded from separate strands, while those of the genera Iteravirus and Brevidensovirus are monosens (encoded from the same strand) and are~5 and 4 kb long, respectively (Jousset et al., 1993;O'Neill et al., 1995;Fauquet et al., 2005).The identification of DNVs in various mosquito cells and wild mosquitoes suggests that the brevidensoviruses have a widespread distribution (O'Neill et al., 1995). The type species of the genus Brevidensovirus is Aedes aegypti densovirus (AaeDNV) (Buchatsky., 1989). The genus contains several other isolates including Aedes albopictus densovirus (AalDNV) [this species contains to date three distinct viruses from C6/36 cells all identified as AalDNV, we shall refer to these in this paper as AalDNV-1 (identified by Jousset et al., 1993;Boublik et al., 1994), AalDNV-2 (identified by Chen et al., 2004) and AalDNV-3 (identified by Paterson et al., 2005)]. Culex pipiens densovirus (CpDNV) was isolated from Culex pipiens larvae; however, it is genetically related to the type speciesThe GenBank/EMBL/DDBJ accession numbers for the sequences reported in this paper are EF579756-EF579771.Supplementary tables are available with the online version of this paper. (2008( ), 89, 195-199 DOI 10.1099 Here we report the isolation and characterization of a ...