Tingsong Hu

Hepatitis virus in long-fingered bats, Myanmar.

During an analysis of the virome of bats from Myanmar, a large number of reads were annotated to orthohepadnaviruses. We present the full genome sequence and a morphological analysis of an orthohepadnavirus circulating in bats. This virus is substantially different from currently known members of the genus Orthohepadnavirus and represents a new species.

Characterization of a novel orthoreovirus isolated from fruit bat, China

BackgroundIn recent years novel human respiratory disease agents have been described for Southeast Asia and Australia. The causative pathogens were classified as pteropine orthoreoviruses with a strong phylogenetic relationship to orthoreoviruses of bat origin.ResultsIn this report, we isolated a novel Melaka-like reovirus (named “Cangyuan virus”) from intestinal content samples of one fruit bat residing in China’s Yunnan province. Phylogenetic analysis of the whole Cangyuan virus genome sequences of segments L, M and S demonstrated the genetic diversity of the Cangyuan virus. In contrast to the L and M segments, the phylogenetic trees for the S segments of Cangyuan virus demonstrated a greater degree of heterogeneity.ConclusionsPhylogenetic analysis indicated that the Cangyuan virus was a novel orthoreovirus and substantially different from currently known members of Pteropine orthoreovirus (PRV) species group.

Emergence of novel clade 2.3.4 influenza A (H5N1) virus subgroups in Yunnan Province, China.

From December 2013 to March 2014, a major wave of highly pathogenic avian influenza outbreak occurred in poultry in Yunnan Province, China. We isolated and characterized eight highly pathogenic avian influenza A (H5N1) viruses from poultry. Full genome influenza sequences and analyses have been performed. Sequence analyses revealed that they belonged to clade 2.3.4 but did not fit within the three defined subclades. The isolated viruses were provisional subclade 2.3.4.4e. The provisional subclade 2.3.4.4e viruses with six internal genes from avian influenza A (H5N2) viruses in 2013 were the novel reassortant influenza A (H5N1) viruses which were associated with the outbreak of H5N1 occurred in egg chicken farms in Yunnan Province. The HA genes were similar to subtype H5 viruses isolated from January to March of 2014 in Asia including H5N6 and H5N8. The NA genes were most closely related to A/chicken/Vietnam/NCVD-KA423/2013 (H5N1) from the subclade 2.3.2. The HI assay demonstrated a lack of antigenic relatedness between clades 2.3.4.4e and 2.3.4.1 (RE-5 vaccine strain) or 2.3.2.2 (RE-6 vaccine strain).

Molecular Characterization of Cryptosporidium in Bats from Yunnan Province, Southwestern China

Abstract: The present study was conducted to investigate the prevalence and genotypes of Cryptosporidium in bats. A total of 247 bats, belonging to Rhinolophus sinicus, Rousettus leschenaultia, Aselliscus stoliczkanus, and Hipposideros fulvus, were collected in Yunnan Province, Southwestern China, and the intestinal tissues were examined for Cryptosporidium infection by PCR amplification of the small subunit ribosomal RNA (SSU rRNA). The overall infection rate was 7.7% (95% CI, 4.5 to 11.0%), with R. sinicus having the highest level at 9.5% (95% CI, 2.8 to 16.1%) followed by A. stoliczkanus at 7.8% (95% CI, 2.2 to 18.9%), H. fulvus at 7.2% (95% CI, 1.1 to 13.4%), and R. leschenaultia at 5.7% (95% CI, 1.2 to 15.7%). DNA sequence and phylogenetic analyses based on SSU rRNA revealed the presence of 2 novel genotypes, designated as Cryptosporidium bat genotype I in A. stoliczkanus and R. sinicus and Cryptosporidium bat genotype II in R. leschenaultia, R. sinicus, and H. fulvus. This is the first report of Cryptosporidium genotypes in bats. Further biological and genetic characterization is needed to determine the relationship of the 2 novel genotypes to established Cryptosporidium species–genotypes.

Identification of a novel orthohepadnavirus in pomona roundleaf bats in China

Bats in Myanmar, Gabon, and Panama have been found to harbor diverse hepadnaviruses. Here, we report a novel hepadnavirus in 4 of 20 pomona roundleaf bats from Yunnan province, China. This virus contains 3,278 nucleotides (nt) in the full circularized genome, with four predicted open frames (ORFs) reading in the same direction. Full genomic sequence comparisons and evolutionary analysis indicate that this virus is a member of a new species within the genus Orthohepadnavirus

Epidemiological and molecular characteristics of emergent dengue virus in Yunnan Province near the China-Myanmar-Laos border, 2013-2015.

BackgroundYunnan Province is located in southwestern China and neighbors the Southeast Asian countries, all of which are dengue-endemic areas. In 2000–2013, sporadic imported cases of dengue fever (DF) were reported almost annually in Yunnan Province. During 2013–2015, we confirmed that a large-scale indigenous DF outbreak emerged in cities of Yunnan Province near the China-Myanmar-Laos border.MethodsEpidemiological characteristics of DF in Yunnan Province during 2013–2015 were evaluated by retrospective analysis. A total of 232 dengue virus (DENV)-positive sera were randomly collected for sequence analysis of the capsid/premembrane region of DENV from patients with DF in Yunnan Province. The envelope gene of DENV isolates was also amplified and sequenced. Phylogenetic analyses were performed using the neighbor-joining method with the Tajima-Nei model.ResultsPhylogenetically, all DENV-positive samples could be classified into DENV-1 genotype I and DENV-2 Asian I genotype during 2013–2015 and DENV-4 genotype I in 2015 from Ruili City; and DENV-3 genotype II in 2013 and DENV-2 Cosmopolitan genotype in 2015 from Xishuangbanna Prefecture.ConclusionsOur results indicated that imported DF from patients from Laos and Myanmar was the primary cause of the DF epidemic in Yunnan Province. Additionally, DENV strains of all four serotypes were identified in indigenous cases in Yunnan Province during the same time period, while the dengue epidemic pattern observed in southwestern Yunnan showed characteristics of a hypoendemic nature: circulation of DENV-1 and DENV-2 over consecutive years.

Group A Rotaviruses in Chinese Bats: Genetic Composition, Serology, and Evidence for Bat-to-Human Transmission and Reassortment

ABSTRACT Bats are natural reservoirs for many pathogenic viruses, and increasing evidence supports the notion that bats can also harbor group A rotaviruses (RVAs), important causative agents of diarrhea in children and young animals. Currently, 8 RVA strains possessing completely novel genotype constellations or genotypes possibly originating from other mammals have been identified from African and Chinese bats. However, all the data were mainly based on detection of RVA RNA, present only during acute infections, which does not permit assessment of the true exposure of a bat population to RVA. To systematically investigate the genetic diversity of RVAs, 547 bat anal swabs or gut samples along with 448 bat sera were collected from five South Chinese provinces. Specific reverse transcription-PCR (RT-PCR) screening found four RVA strains. Strain GLRL1 possessed a completely novel genotype constellation, whereas the other three possessed a constellation consistent with the MSLH14-like genotype, a newly characterized group of viruses widely prevalent in Chinese insectivorous bats. Among the latter, strain LZHP2 provided strong evidence of cross-species transmission of RVAs from bats to humans, whereas strains YSSK5 and BSTM70 were likely reassortants between typical MSLH14-like RVAs and human RVAs. RVA-specific antibodies were detected in 10.7% (48/448) of bat sera by an indirect immunofluorescence assay (IIFA). Bats in Guangxi and Yunnan had a higher RVA-specific antibody prevalence than those from Fujian and Zhejiang provinces. These observations provide evidence for cross-species transmission of MSLH14-like bat RVAs to humans, highlighting the impact of bats as reservoirs of RVAs on public health. IMPORTANCE Bat viruses, such as severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS), Ebola, Hendra, and Nipah viruses, are important pathogens causing outbreaks of severe emerging infectious diseases. However, little is known about bat viruses capable of causing gastroenteritis in humans, even though 8 group A viruses (RVAs) have been identified from bats so far. In this study, another 4 RVA strains were identified, with one providing strong evidence for zoonotic transmission from bats to humans. Serological investigation has also indicated that RVA infection in bats is far more prevalent than expected based on the detection of viral RNA.

Detection and characterization of diverse alpha- and betacoronaviruses from bats in China

Bats have been implicated as important reservoir hosts of alpha- and betacoronaviruses. In this study, diverse coronaviruses (CoVs) were detected in 50 of 951 (positive rate 5.3%) intestinal specimens of eight bat species collected in four provinces and the Tibet Autonomous Region of China by pan-coronavirus RT-PCR screening. Based on 400-nt RNA-dependent RNA polymerase (RdRP) sequence analysis, eight belonged to genus Alphacoronavirus and 42 to Betacoronavirus. Among the 50 positive specimens, thirteen gave rise to CoV full-length RdRP gene amplification for further sequence comparison, of which three divergent sequences (two from a unreported province) were subjected to full genome sequencing. Two complete genomes of betacoronaviruses (JTMC15 and JPDB144) and one nearly-complete genome of alphacoronavirus (JTAC2) were sequenced and their genomic organization predicted. The present study has identified additional numbers of genetically diverse bat-borne coronaviruses with a wide distribution in China. Two new species of bat CoV, identified through sequence comparison and phylogenetic analysis, are proposed.

Fatal influenza A (H5N1) virus Infection in zoo-housed Tigers in Yunnan Province, China

From 2014 to 2015, three cases of highly pathogenic avian influenza infection occurred in zoo-housed north-east China tigers (Panthera tigris ssp.altaica) and four tigers died of respiratory distress in succession in Yunnan Province, China. We isolated and characterized three highly pathogenic avian influenza A(H5N1) viruses from these tigers. Phylogenetic analysis indicated that A/tiger /Yunnan /tig1404 /2014(H5N1) belongs to the provisional subclade 2.3.4.4e which were novel reassortant influenza A (H5N1) viruses with six internal genes from avian influenza A (H5N2) viruses. The HA gene of the isolated A/tiger /Yunnan /tig1412 /2014(H5N1) virus belongs to the subclade 2.3.2.1b. The isolated A/tiger /Yunnan /tig1508/2015 (H5N1) virus was a novel reassortant influenza A (H5N1) virus with three internal genes (PB2, PB1 and M) from H9N2 virus and belongs to the subclade 2.3.2.1c.

Molecular and serological evidence for Seoul virus in rats (Rattus norvegicus) in Zhangmu, Tibet, China

We report the detection of a virus, tentatively identified as Seoul virus (SEOV), from a rat (Rattus norvegicus) collected in the city of Zhangmu, Tibet. SEOV RNA was detected in lung tissue by reverse transcription (RT)-PCR, followed by sequencing. Serum samples collected from Zhangmu were positive for SEOV-specific antibodies (indirect fluorescent antibody test that used SEO antigen). Sequencing and phylogenetic analysis of partial L and S sequences together with serology results suggest that the Zhangmu01 hantavirus is an isolate of SEOV, that hantaviruses circulate in Tibet, and that rats may act as natural reservoirs for the virus.