Metagenomic study of the viruses of African straw-coloured fruit bats: detection of a chiropteran poxvirus and isolation of a novel adenovirus

Genetic Diversity and Geographic Spread of Henipaviruses

Henipaviruses, such as Hendra and Nipah viruses, are major zoonotic pathogens that cause encephalitis and respiratory infections in humans and animals. The recent emergence of Langya virus in China highlights the need to understand henipavirus host diversity and geographic spread to prevent future outbreaks. Our analysis of the National Center for Biotechnology Information Virus and VIRION databases revealed ≈1,117 henipavirus sequences and 142 complete genomes. Bats (64.7%) and shrews (11.7%) dominated the host species record, and the genera Pteropus and Crocidura contained key henipavirus hosts in Asia, Australia, and Africa. Henipaviruses found in the Eidolon bat genus exhibited the highest within-host genetic distance. Phylogenetic analysis revealed batborne and rodent- or shrew-derived henipaviruses diverged ≈11,000 years ago and the first known lineage originating in Eidolon genus bats ≈9,900 years ago. Pathogenic henipaviruses diverged from their ancestors 2,800-1,200 years ago. Including atypical hosts and regions in future investigations is necessary to control future outbreaks.

Visible and rapid detection of feline chaphamaparvovirus using multienzyme isothermal rapid amplification and lateral flow dipstick assay

Feline chaphamaparvovirus (FeChPV) is a novel parvovirus previously reported in Canadian cats and Chinese dogs with diarrhea in 2019 and 2020, respectively. Herein, we aimed to establish a simple detection method for FeChPV in field clinics. The primers and probes for the multienzyme isothermal rapid amplification and lateral flow dipstick (MIRA-LFD) assay were designed to target the conserved regions of the FeChPV genome and determine the optimal reaction temperature and time. Without relying on precision instruments, FeChPV detection using the MIRA-LFD assay was completed within 20 min at 37°C, without any cross-reaction with other reference viruses. The newly established MIRA-LFD assay had a detection limit of 32.3 copies/μL, which was 10-fold lower than that of the nested polymerase chain reaction (PCR) assay. Furthermore, the MIRA-LFD assay detected 29 FeChPV-positive samples among 417 cats with diarrhea, providing a slightly higher positivity rate than the nested PCR assay. These results indicate that the newly developed MIRA-LFD assay for FeChPV detection is an efficient, economical, reliable, and simple method that can help in the early prevention and control of FeChPV infection.

Genomic characterization of novel bat kobuviruses in Madagascar: implications for viral evolution and zoonotic risk

Kobuviruses (family Picornaviridae, genus Kobuvirus) are enteric viruses that infect a wide range of both human and animal hosts. Much of the evolutionary history of kobuviruses remains elusive, largely due to limited screening in wildlife. Bats have been implicated as major sources of virulent zoonoses, including coronaviruses, henipaviruses, and filoviruses, though much of the bat virome still remains uncharacterized. While most bat virus research has historically focused on immediately recognizable zoonotic clades (e.g. SARS-related coronaviruses), a handful of prior reports catalog kobuvirus infection in bats and posit the role of bats as potential progenitors of downstream kobuvirus evolution. As part of a multi-year study, we carried out metagenomic Next Generation Sequencing (mNGS) on fecal samples obtained from endemic, wild-caught Madagascar fruit bats to characterize potentially zoonotic viruses circulating within these populations. The wild bats of Madagascar represent diverse Asian and African phylogeographic histories, presenting a unique opportunity for viruses from disparate origins to mix, posing significant public health threats. Here, we report detection of kobuvirus RNA in Malagasy fruit bat (Eidolon dupreanum) feces and undertake phylogenetic characterization of one full genome kobuvirus sequence, which nests within the Aichivirus A clade - a kobuvirus clade known to infect a wide range of hosts including humans, rodents, canids, felids, birds, and bats. Given the propensity of kobuviruses for recombination and cross-species infection, further characterization of this clade is critical to accurate evaluation of future zoonotic threats.

European Hedgehogs as Hosts of Chaphamaparvovirus, Italy

In 2022, a novel parvovirus was identified from an outbreak of fatal enteritis in weaned European hedgehogs (Erinaceus europaeus) at a wildlife rescue center in Southern Italy. During sequence analysis, the strain was found to be closely related (90.4% nucleotide identity) to a chaphamaparvovirus (ChPV) discovered in Amur hedgehogs (Erinaceus amurensis) during a large metaviromic investigation in game animals in China. In this study, we investigated the presence of this novel ChPV in necropsied European hedgehogs from different areas of North-Western Italy. Duodenal and liver samples collected from 194 necropsied hedgehogs were screened by using a specific quantitative PCR. A total of 38/194 animals (19.6%) tested positive, with ChPV DNA being detected in the duodenum (9.3%, 18/194), liver (7.2%, 14/194) or in both (3.1%, 6/194) tissue samples, with comparable rates and mean viral loads. The nearly full-length genome of four hedgehog ChPV strains was reconstructed. During phylogenetic analysis based on the NS1 and partial VP aa sequences, the four strains detected in this study tightly clustered with the prototype ChPVs previously identified in Amur and European hedgehogs within a potential novel candidate species of the genus Chaphamaparvovirus.

Unveiling bat-borne viruses: a comprehensive classification and analysis of virome evolution

BACKGROUND

Bats (Order Chiroptera) are an important reservoir of emerging zoonotic microbes, including viruses of public health concern such as henipaviruses, lyssaviruses, and SARS-related coronaviruses. Despite the continued discovery of new viruses in bat populations, a significant proportion of these viral agents remain uncharacterized, highlighting the imperative for additional research aimed at elucidating their evolutionary relationship and taxonomic classification.

RESULTS

In order to delve deeper into the viral reservoir hosted by bats, the present study employed Next Generation Sequencing (NGS) technology to analyze 13,105 swab samples obtained from various locations in China. Analysis of 378 sample pools revealed the presence of 846 vertebrate-associated viruses. Subsequent thorough examination, adhering to the International Committee on Taxonomy of Viruses (ICTV) criteria for virus classification, identified a total of 120 putative viral species with the potential to emerge as novel viruses, comprising a total of 294 viral strains. Phylogenetic analysis of conserved genomic regions indicated the novel virus exhibited a diverse array of viral lineages and branches, some of which displayed close genetic relationships to known human and livestock pathogens, such as poxviruses and pestiviruses.

CONCLUSIONS

This study investigates the breadth of DNA and RNA viruses harbored by bats, delineating several novel evolutionary lineages and offering significant contributions to virus taxonomy. Furthermore, the identification of hitherto unknown viruses with relevance to human and livestock health underscores the importance of this study in encouraging infectious disease monitoring and management efforts in both public health and veterinary contexts. Video Abstract.

Eptesipox virus-associated lesions in naturally infected big brown bats

Bats have many unique qualities amongst mammals; one of particular importance is their reported tolerance to viruses without developing disease. Here, the authors present evidence to the contrary by describing and demonstrating viral nucleic acids within lesions from eptesipox virus (EfPV) infection in big brown bats. One hundred and thirty bats submitted for necropsy from Saskatchewan, Canada, between 2017 and 2021 were screened for EfPV by polymerase chain reaction (PCR); 2 had amplifiable poxvirus DNA. The lesions associated with infection were oral and pharyngeal ulcerations and joint swelling in 2/2 and 1/2 cases, respectively. These changes were nonspecific for poxvirus infection, although intracytoplasmic viral inclusion bodies within the epithelium, as observed in 2/2 bats, are diagnostic when present. Viral nucleic acids, detected by in situ hybridization (ISH), were observed in the epithelium adjacent to ulcerative lesions from both cases and within the joint proliferation of 1 case. A new isolate of EfPV was obtained from 1 case and its identity was confirmed with electron microscopy and whole genome sequencing. Juxtanuclear replication factories were observed in most cells; however, rare intranuclear virus particles were also observed. The significance of the presence of virus particles within the nucleus is uncertain. Whole genome assembly indicated that the nucleotide sequence of the genome of this EfPV isolate was 99.7% identical to a previous isolate from big brown bats in Washington, USA between 2009 and 2011. This work demonstrates that bats are not resistant to the development of disease with viral infections and raises questions about the dogma of poxvirus intracytoplasmic replication.

Molecular epidemiological investigation and recombination analysis of Cachavirus prevalent in China

Chaphamaparvovirus carnivoran1 (canine Chaphamaparvovirus, also known as Cachavirus [CachaV]) is a novel parvovirus first reported in dog feces collected from the United States in 2017 and China in 2019. To continuously track its infection and evolution status, 276 canine anal swabs were obtained from pet hospitals in central, northern, and eastern China between 2021 and 2023 and screened via polymerase chain reaction; subsequently, a systematic study was conducted. Of these samples, nine (3.3%) were positive for CachaV. Using polymerase chain reaction, whole genome sequences of the nine CachaV-positive strains were amplified. The NS1 amino acid sequence identity between CachaV strains from China and other countries was 96.23-99.85%, whereas the VP1 protein sequence identity was 95.83-100%. CHN230521 demonstrated the highest identity for NS1 amino acids (99.85%) and VP1 amino acids (100%) with NWT-W88 and CP-T015. According to the model prediction of CHN220916-VP1 protein, Met64Thr, Thr107Ala, and Phe131Ser mutations may cause tertiary structural changes in VP1 protein. Interestingly, each of the nine CachaV strains harbored the same site mutations in NS1 (Ser252Cys, Gly253Leu, and Gly254Thr). Although no explicit recombination events were predicted, the clustering and branching of the phylogenetic tree were complicated. Based on the evolution trees for VP1 and NS1, the nine CachaV strains identified from 2021 to 2023 were closely related to those identified in gray wolves and cats. This study may be beneficial for evaluating the prevalence of CachaVs in China, thereby understanding the evolution trend of CachaVs.

Pteropox infection in a juvenile grey-headed flying fox (Pteropus poliocephalus)

A juvenile grey-headed flying fox (GHFF) (Pteropus poliocephalus) presented to the Australia Zoo Wildlife Hospital after a wildlife carer found the animal hanging on the outside of an aviary. On presentation, the animal was emaciated and moribund with disseminated, multifocal, depigmented and proliferative lesions on the wing membranes and skin of the neck. Histopathology revealed multiple, well-circumscribed proliferative epidermal lesions with intracytoplasmic inclusion bodies. A poxvirus was identified via transmission electron microscopy and next-generation sequencing (NGS). Analysis of sequences obtained demonstrated 99% nucleotide identity to Pteropox virus strain Australia (GenBank KU980965). To the authors' knowledge, this paper describes the first case of Pteropox virus infection in a GHFF.

Virome analysis of Desmodus rotundus tissue samples from the Amazon region

BACKGROUND

Bats are renowned for harboring a high viral diversity, their characteristics contribute to emerging infectious diseases. However, environmental and anthropic factors also play a significant role in the emergence of zoonotic viruses. Metagenomic is an important tool for investigating the virome of bats and discovering new viruses.

RESULTS

Twenty-four families of virus were detected in lung samples by sequencing and bioinfomatic analysis, the largest amount of reads was focused on the Retroviridae and contigs assembled to Desmodus rotundus endogenous retrovirus, which was feasible to acquire complete sequences. The reads were also abundant for phages.

CONCLUSION

This lung virome of D. rotundus contributes valuable information regarding the viral diversity found in bats, which is useful for understanding the drivers of viral cycles and their ecology in this species. The identification and taxonomic categorization of viruses hosted by bats carry epidemiological significance due to the potential for viral adaptation to other animals and humans, which can have severe repercussions for public health. Furthermore, the characterization of endogenized viruses helps to understanding the host genome and the evolution of the species.

Main causes of death of free-ranging bats in Turin province (North-Western Italy): gross and histological findings and emergent virus surveillance

BACKGROUND

Bats are recognized as reservoir species for multiple viruses. However, little is known on bats' health and mortality. Thus, this study aimed to investigate the main causes of death of bats from Turin province (North-western Italy) and to describe gross and histopathological lesions potentially associated with the presence of selected bat viruses.

RESULTS

A total of 71 bats belonging to 9 different species of the families Vespertilionidae and Molossidae were necropsied and samples of the main organs were submitted to histopathological examination. Also, aliquots of the small intestine, liver, spleen, lung, and brain were collected and submitted to biomolecular investigation for the identification of Coronaviridae, Poxviridae, Reoviridae (Mammalian orthoreovirus species), Rhabdoviridae (Vaprio ledantevirus and Lyssavirus species) and Kobuvirus. The majority of bats died from traumatic lesions due to unknown trauma or predation (n = 40/71, 56.3%), followed by emaciation (n = 13/71,18.3%). The main observed gross lesions were patagium and skin lesions (n = 23/71, 32.4%), forelimbs fractures (n = 15/71, 21.1%) and gastric distension (n = 10/71,14.1%). Histologically, the main lesions consisted of lymphoplasmacytic pneumonia (n = 24/71, 33.8%), skin/patagium dermatitis (n = 23/71, 32.4%), liver steatosis and hepatitis (n = 12, 16.9%), and white pulp depletion in the spleen (n = 7/71, 9.8%). Regarding emergent bat viruses, only poxvirus (n = 2, 2.8%) and orthoreovirus (n = 12/71, 16.9%) were detected in a low percentage of bats.

CONCLUSIONS

Trauma is the main lesion observed in bats collected in Turin province (North-western Italy) associated with forelimb fractures and the detected viral positivity rate seems to suggest that they did not represent a threat for human health.

Molecular identification of carnivore chaphamaparvovirus 2 (feline chaphamaparvovirus) in cats with diarrhea from China

Chaphamaparvovirus carnivoran2 (feline chaphamaparvovirus, FeChPV) is a novel feline parvovirus originally detected in Canadian cats in 2019, and it has also been identified in domestic cats in other nations. To evaluate the prevalence and genetic diversity of FeChPV in China, rectal swabs of pet cats from Henan, Guangdong, Anhui, Zhejiang, and Inner Mongolia provinces were collected. Of the 230 samples subjected to nested polymerase chain reaction, 6 (2.6%) tested positive for FeChPV. Although all positive samples were from cats with diarrhea, statistical analyses revealed no correlation between the presence of the virus and clinical symptoms (p > 0.05). Phylogenetic trees of nonstructural protein 1 (NS1) and capsid protein (VP1) demonstrated that these six new strains formed a major branch with other reference FeChPV strains and considerably differed from Chaphamaparvoviru carnivoran1. Moreover, recombination analysis revealed that the FeChPV strain CHN20201025, previously detected in a dog, was a recombinant and strains CHN200228 and CHN180917, identified in this study, were the closest relatives to the parental strains. The findings of this study and a previous study wherein FeChPV was detected in dogs suggest that FeChPV can propagate between species. Additionally, these findings indicate that the genetic diversity of FeChPV can provide an insight into the epidemiological status of FeChPV in China.

The prevalence, genetic diversity and evolutionary analysis of cachavirus firstly detected in northeastern China

Canine cachavirus is a novel parvovirus belonging to the genus Chaphamaparvovirus that was first detected in dogs in the United States. However, our knowledge of the prevalence and genetic characteristics of cachavirus is relatively limited. In this study, 325 canine fecal specimens collected from healthy and diarrheic dogs in northeastern China were screened with PCR. Twenty-two of the 325 (6.8%) samples were positive for cachavirus. The diarrhea samples showed high viral coinfection rates, and we detected coinfections with canine astrovirus (CaAstV) and cachavirus for the first time. A sequence analysis revealed that the Chinese cachavirus strains have point mutations in four consecutive amino acid codons relative to the original American strain. A codon usage analysis of the VP1 gene showed that most preferred codons in cachavirus were A- or T-ending codons, as in traditional canine parvovirus 2. A co-evolutionary analysis showed that cachavirus has undergone cospeciation with its hosts and has been transmitted among different host species. Our findings extend the limited cachavirus sequences available, and provide detailed molecular characterization of the strains in northeastern China. Further epidemiological surveillance is required to determine the significance and evolution of cachavirus.

Surveillance, Isolation, and Genetic Characterization of Bat Herpesviruses in Zambia

Bats are of significant interest as reservoirs for various zoonotic viruses with high diversity. During the past two decades, many herpesviruses have been identified in various bats worldwide by genetic approaches, whereas there have been few reports on the isolation of infectious herpesviruses. Herein, we report the prevalence of herpesvirus infection of bats captured in Zambia and genetic characterization of novel gammaherpesviruses isolated from striped leaf-nosed bats (Macronycteris vittatus). By our PCR screening, herpesvirus DNA polymerase (DPOL) genes were detected in 29.2% (7/24) of Egyptian fruit bats (Rousettus aegyptiacus), 78.1% (82/105) of Macronycteris vittatus, and one Sundevall's roundleaf bat (Hipposideros caffer) in Zambia. Phylogenetic analyses of the detected partial DPOL genes revealed that the Zambian bat herpesviruses were divided into seven betaherpesvirus groups and five gammaherpesvirus groups. Two infectious strains of a novel gammaherpesvirus, tentatively named Macronycteris gammaherpesvirus 1 (MaGHV1), were successfully isolated from Macronycteris vittatus bats, and their complete genomes were sequenced. The genome of MaGHV1 encoded 79 open reading frames, and phylogenic analyses of the DNA polymerase and glycoprotein B demonstrated that MaGHV1 formed an independent lineage sharing a common origin with other bat-derived gammaherpesviruses. Our findings provide new information regarding the genetic diversity of herpesviruses maintained in African bats.

Old and Novel Enteric Parvoviruses of Dogs

Parvovirus infections have been well known for around 100 years in domestic carnivores. However, the use of molecular assays and metagenomic approaches for virus discovery and characterization has led to the detection of novel parvovirus species and/or variants in dogs. Although some evidence suggests that these emerging canine parvoviruses may act as primary causative agents or as synergistic pathogens in the diseases of domestic carnivores, several aspects regarding epidemiology and virus-host interaction remain to be elucidated.

Molecular Characterization of Feline Chaphamaparvovirus (Carnivore chaphamaparvovirus 2) Firstly Detected in Dogs from China

A new type of parvovirus known as feline chaphamaparvovirus (FeChPV) was discovered in the feces of shelter cats in Canada in 2019, and >50% of cats were reported to be infected with this virus. In this study, two FeChPV-positive samples were identified from the rectal swabs of 285 dogs with diarrhea but none in 50 healthy dogs. Whole genome sequences of these two FeChPV strains (OQ162042 and OQ162043) were amplified and compared with those of the two viruses originally discovered in Canada (IDEXX-1 and VRI849). The whole genome, NS1, and VP1 of the two FeChPV strains shared a high identity of 95.0%–97.8% nucleotide, 96.9%–98.6% amino acid (aa), and 97.2%–98.8% aa with the reported FeChPV strains, respectively. The phylogenetic tree of NS1 and VP1 revealed that two FeChPV strains, namely, CHN20201025 and CHN20201226, were closely clustered with the two FeChPV prototypes detected in Canada in a group. Moreover, CHN20201025 and CHN20201226 were obviously different from Carnivore chaphamaparvovirus 1 and were classified as Carnivore chaphamaparvovirus 2. This is the first study to report the identification of FeChPV in fecal samples from dogs in China, and the genetic analysis of the FeChPV, which was previously detected in Canadian cats, would improve our understanding of its host spectrum.

Otus scops adenovirus: the complete genome sequence of a novel aviadenovirus discovered in a wild owl

We present the complete genome sequence of an aviadenovirus obtained by metagenomics from cloacal swabs taken from a free-living Eurasian scops owl (Otus scops, a small raptor distributed in Europe and several parts of Asia) in China. Thirty protein coding genes were predicted in this 40,239-bp-long genome, which encodes the largest fiber protein among all reported aviadenoviruses. The viral genome sequence is highly divergent, and the encoded proteins have an average of only 55% amino acid sequence identity to those of other adenoviruses. In phylogenetic analysis, the new owl virus grouped with members of the genus Aviadenovirus and formed a common clade with another owl adenovirus reported previously in Japan. This is the second complete genome sequence of an aviadenovirus discovered in owls, and its proteins have an average of 62% amino acid sequence identity to those of the previously reported owl adenovirus. Combining this result with comparative genomic analysis of all aviadenoviruses, we propose that this owl virus and the previously described Japanese owl adenovirus can be assigned to two new species in the genus Aviadenovirus. This study provides new data on the diversity of aviadenoviruses in wild birds.

Molecular characteristics of novel chaphamaparvovirus identified in chickens

Chicken chaphamaparvovirus (CkChpV) is a novel parvovirus species that belongs to the Chaphamaparvovirus genus and is frequently detected in different vertebrates exhibiting diarrhea symptoms. In this study, screening tests were performed on samples from 478 chickens, including 357 with diarrhea and 121 healthy, collected from 25 farms in China to investigate CkChpV infection in China. CkChpV, avian nephritis virus, rotavirus, chicken parvovirus, Newcastle disease virus, infectious bronchitis virus, chicken proventricular necrosis virus, and chicken circovirus were all detected in the samples at a positivity rate of 32%, 9%, 6%, 2%, 2%, 1%, 0%, and 0%, respectively. Statistical analyses suggested a correlation between the infection by the virus and diarrhea (P < 0.05). The genome of 9 strains from the CkChpV-positive samples, whose length was 4,432 nucleotides, have been completely sequenced. The strains shared 97.2 to 98.7% genomic similarity, 98.1 to 99.1%, and 98.2 to 99.2% amino acid similarity, respectively, for NS1 and VP1 compared with CkChpV strain RS/BR/15/2S in GenBank. The genetic relationship between these strains and CkChpV was established through phylogenetic analysis. These findings indicated the infection existence of CkChpV in China, which enriches our understanding of the diversity of the chaphamaparvoviruses and its host spectrum.

Detection of FeChPV in a cat shelter outbreak of upper respiratory tract disease in China

Feline parvovirus often causes a fatal infectious disease and has a serious impact on domestic cats and wild felines. Feline chaphamaparvovirus (FeChPV) is a novel type of feline parvovirus that has been successively identified in Canada, Italy, and Turkey. The prevalence and pathogenicity of FeChPV in other regions is still unknown. In this study, we recorded the detection of FeChPV in a cat shelter in China. A high prevalence (81.08%, 30/37) of FeChPV was detected in cats with symptoms of upper respiratory tract disease (URTD) in this cat shelter. Multiple pathogen testing indicated high coinfection rates of 80% (24/30) with other common viruses in FeChPV-positive cats. Analyses of the necropsy and histopathological findings revealed severe lymphadenitis, encephalitis, and viral DNA in several tissues (including brain) of the deceased cat. Finally, we obtained nearly full-length genomes of four strains with 98.4%~98.6% homology with previously reported genomes. Notably, VP1 proteins showed seven unique amino acid mutations, while NS1 proteins carried eight mutations. In the evolutionary tree based on VP1 and NS1, the sequences clustered in a large branch with Italian and Canadian FeChPV strains. Given the possible association of FeChPV with URTD, further studies are necessary to evaluate the pathogenicity and epidemiological characteristics of this novel feline pathogen.

Adaptive duplication and genetic diversification of protein kinase R contribute to the specificity of bat-virus interactions

Several bat species act as asymptomatic reservoirs for many viruses that are highly pathogenic in other mammals. Here, we have characterized the functional diversification of the protein kinase R (PKR), a major antiviral innate defense system. Our data indicate that PKR has evolved under positive selection and has undergone repeated genomic duplications in bats in contrast to all studied mammals that have a single copy of the gene. Functional testing of the relationship between PKR and poxvirus antagonists revealed how an evolutionary conflict with ancient pathogenic poxviruses has shaped a specific bat host-virus interface. We determined that duplicated PKRs of the Myotis species have undergone genetic diversification, allowing them to collectively escape from and enhance the control of DNA and RNA viruses. These findings suggest that viral-driven adaptations in PKR contribute to modern virus-bat interactions and may account for bat-specific immunity.

Myotis fimbriatus Virome, a Window to Virus Diversity and Evolution in the Genus Myotis

Significant efforts have been made to characterize viral diversity in bats from China. Many of these studies were prospective and focused mainly on Rhinolophus bats that could be related to zoonotic events. However, other species of bats that are part of ecosystems identified as virus diversity hotspots have not been studied in-depth. We analyzed the virome of a group of Myotis fimbriatus bats collected from the Yunnan Province during 2020. The virome of M. fimbriatus revealed the presence of families of pathogenic viruses such as Coronavirus, Astrovirus, Mastadenovirus, and Picornavirus, among others. The viral sequences identified in M. fimbriatus were characterized by significant divergence from other known viral sequences of bat origin. Complex phylogenetic landscapes implying a tendency of co-specificity and relationships with viruses from other mammals characterize these groups. The most prevalent and abundant virus in M. fimbriatus individuals was an alphacoronavirus. The genome of this virus shows evidence of recombination and is likely the product of ancestral host-switch. The close phylogenetic and ecological relationship of some species of the Myotis genus in China may have played an important role in the emergence of this alphacoronavirus.

Differential Viral Genome Diversity of Healthy and RSS-Affected Broiler Flocks

The intestinal virus community contributes to health and disease. Runting and stunting syndrome (RSS) is associated with enteric viruses and leads to economic losses in the poultry industry. However, many viruses that potentially cause this syndrome have also been identified in healthy animals. To determine the difference in the virome of healthy and diseased broilers, samples from 11 healthy and 17 affected broiler flocks were collected at two time points and analyzed by Next-Generation Sequencing. Virus genomes of Parvoviridae, Astroviridae, Picornaviridae, Caliciviridae, Reoviridae, Adenoviridae, Coronaviridae, and Smacoviridae were identified at various days of poultry production. De novo sequence analysis revealed 288 full or partial avian virus genomes, of which 97 belonged to the novel genus Chaphamaparvovirus. This study expands the knowledge of the diversity of enteric viruses in healthy and RSS-affected broiler flocks and questions the association of some viruses with the diseases.

Genomic characteristics and pathogenicity of a new bat adenoviruses strains that was isolated in at sites along the southeastern coasts of the P. R. of China from 2015 to 2019

Bats are important reservoirs for many kinds of emerging zoonotic viruses. In order to explore potential pathogens carried by bats and trace the source of adenovirus outbreaks on the southeastern coast of China, we took pharyngeal and anal swabs from a total of 552 bats (Rhinolophus pusillus) collected from various areas of Chinese southeastern coast. Adenoviruses were identified in 36 out of the 552 samples (6.5%) . Complete genome sequences of two adenovirus isolations from Vero E6 cells were obtained, which were further validated as identical strains via next-generation sequencing and were named Bat-Advcxc6. The cell culture inoculated with the two samples exhibited remarkable cytopathic changes. The full genome has 37,315 bp and owns 29 open reading frames. Phylogenetic analyses confirmed that Bat-Advcxc6 represented a novel bat adenovirus species in the genus Mastadenovirus. Transmission electron microgram showed clear virus particles. Bat-Advcxc6 shared similar characteristics of G + C contents with Bat mastadenovirus WIV11 (Bat mastadenovirus C) found in China in 2016, but differed from this serotype due to a <75% similarity with DNA polymerase amino acid sequences in WIV11. As it is a newly found adenovirus strain according to the international classification criteria, further analyses of virus dynamics, epithelial invasion, and immunization assays are required to explore its potential threats of cross-species transmission.

Molecular and Phylogenetic Characterisation of a Highly Divergent Novel Parvovirus (Psittaciform Chaphamaparvovirus 2) in Australian Neophema Parrots

Parvoviruses under the genus Chaphamaparvovirus (subfamily Hamaparvovirinae) are highly divergent and have recently been identified in many animals. However, the detection and characterisation of parvoviruses in psittacine birds are limited. Therefore, this study reports a novel parvovirus, tentatively named psittaciform chaphamaparvovirus 2 (PsChPV-2) under the genus Chaphamaparvovirus, which was identified in Australian Neophema birds. The PsChPV-2 genome is 4371 bp in length and encompasses four predicted open-reading frames, including two major genes, a nonstructural replicase gene (NS1), and a structural capsid gene (VP1). The NS1 and VP1 genes showed the closest amino acid identities of 56.2% and 47.7%, respectively, with a recently sequenced psittaciform chaphamaparvovirus 1 from a rainbow lorikeet (Trichoglossus moluccanus). Subsequent phylogenetic analyses exhibited that the novel PsChPV-2 is most closely related to other chaphamaparvoviruses of avian origin and has the greatest sequence identity with PsChPV-1 (60.6%). Further systematic investigation is warranted to explore the diversity with many avian-associated parvoviruses likely to be discovered.

Retroviruses of Bats: a Threat Waiting in the Wings?

Bats are infamous reservoirs of deadly human viruses. While retroviruses, such as the human immunodeficiency virus (HIV), are among the most significant of virus families that have jumped from animals into humans, whether bat retroviruses have the potential to infect and cause disease in humans remains unknown. Recent reports of retroviruses circulating in bat populations builds on two decades of research describing the fossil records of retroviral sequences in bat genomes and of viral metagenomes extracted from bat samples. The impact of the global COVID-19 pandemic demands that we pay closer attention to viruses hosted by bats and their potential as a zoonotic threat. Here we review current knowledge of bat retroviruses and explore the question of whether they represent a threat to humans.

First detection of feline bocaparvovirus 2 and feline chaphamaparvovirus in healthy cats in Turkey

The pet cat’s population and the number of viruses that infect them are increasing worldwide. Recently, feline chaphamaparvovirus (FeChPV, also called fechavirus) and feline bocaparvovirus (FBoV) infections, which are novel parvovirus species, have been reported in cats from different geographic regions. Here, we investigated FBoV 1–3 and FeChPVs in healthy cats in Turkey using PCR, where nuclear phosphoprotein 1 (NP1) is targeted for FBoV and NP for FeChPV. For this purpose, oropharygeal swabs were obtained from 70 healthy cats with different housing status from June 15 to December 1, 2020. After PCR screening tests, six out of 70 cats (5/47 shelter cats; 1/23 domestic cats) were found to be positive for FBOV, while two were positive for FeChPV (1/47 shelter cats; 1/23 domestic cats). No cat was found in which both viruses were detected. The nucleotide (nt) sequence comparison in the 310 base pair (bp) NP gene of the two FeChPVs identified in this study shared a high identity with each other (95.0% nt and 99% aa identities) and with previously reported FeChPVs (92.4–97.1% nt and 98.1–99.0% aa identities), including 313R/2019/ITA, 49E/2019/ITA, VRI_849, 284R/2019/ITA, and IDEXX-1. Here, the near-full length (1489 nt, 495 amino acids-aa) of the VP2 gene of the FechaV/Tur-2020/68 isolate obtained from the study was also sequenced. The nt and aa identity ratio of this isolate with other FeChPVs was 98.0–98.5%-96–96.5%, respectively. Sequences of the 465 bp NP1 gene of the six Turkish FBoV strains shared high identities with each other (99.6–100% nt and 99.3–100% aa identities) and with those of FBoV-2 strains (97.8–99.1% nt and 98.0–100% aa identities), including 16SY0701, 17CC0505-BoV2, HFXA-6, and POR1. All FBoVs detected in this study were classified as genotype 2, similar to the study conducted in Japan and Portugal. Here, the NS1 (partial), NP1, VP1 and VP2 gene of the FBoV-2/TUR/2020–14 strain obtained from the study were also sequenced and the nt and aa sequences showed high identities to the above-mentioned FBoV-2 strain/isolates (> 96%, except for the aa ratio of strain 16SY0701). In conclusion, this study shows that FBoV and FeChPV are present in healthy cats in Turkey, and these viruses can be detected from oropharyngeal swabs. Our findings contribute to further investigation of the prevalence, genotype distribution, and genetic diversity of Turkish FBoVs and FeChPVs, adding to the molecular epidemiology of FBoV and FeChPVs worldwide.

Optimizing noninvasive sampling of a zoonotic bat virus

Outbreaks of infectious viruses resulting from spillover events from bats have brought much attention to bat-borne zoonoses, which has motivated increased ecological and epidemiological studies on bat populations. Field sampling methods often collect pooled samples of bat excreta from plastic sheets placed under-roosts. However, positive bias is introduced because multiple individuals may contribute to pooled samples, making studies of viral dynamics difficult. Here, we explore the general issue of bias in spatial sample pooling using Hendra virus in Australian bats as a case study. We assessed the accuracy of different under-roost sampling designs using generalized additive models and field data from individually captured bats and pooled urine samples. We then used theoretical simulation models of bat density and under-roost sampling to understand the mechanistic drivers of bias. The most commonly used sampling design estimated viral prevalence 3.2 times higher than individual-level data, with positive bias 5-7 times higher than other designs due to spatial autocorrelation among sampling sheets and clustering of bats in roosts. Simulation results indicate using a stratified random design to collect 30-40 pooled urine samples from 80 to 100 sheets, each with an area of 0.75-1 m2, and would allow estimation of true prevalence with minimum sampling bias and false negatives. These results show that widely used under-roost sampling techniques are highly sensitive to viral presence, but lack specificity, providing limited information regarding viral dynamics. Improved estimation of true prevalence can be attained with minor changes to existing designs such as reducing sheet size, increasing sheet number, and spreading sheets out within the roost area. Our findings provide insight into how spatial sample pooling is vulnerable to bias for a wide range of systems in disease ecology, where optimal sampling design is influenced by pathogen prevalence, host population density, and patterns of aggregation.

New approaches for metagenome assembly with short reads

In recent years, the use of longer range read data combined with advances in assembly algorithms has stimulated big improvements in the contiguity and quality of genome assemblies. However, these advances have not directly transferred to metagenomic data sets, as assumptions made by the single genome assembly algorithms do not apply when assembling multiple genomes at varying levels of abundance. The development of dedicated assemblers for metagenomic data was a relatively late innovation and for many years, researchers had to make do using tools designed for single genomes. This has changed in the last few years and we have seen the emergence of a new type of tool built using different principles. In this review, we describe the challenges inherent in metagenomic assemblies and compare the different approaches taken by these novel assembly tools.

Towards a more healthy conservation paradigm: integrating disease and molecular ecology to aid biological conservation†

Parasites, and the diseases they cause, are important from an ecological and evolutionary perspective because they can negatively affect host fitness and can regulate host populations. Consequently, conservation biology has long recognized the vital role that parasites can play in the process of species endangerment and recovery. However, we are only beginning to understand how deeply parasites are embedded in ecological systems, and there is a growing recognition of the important ways in which parasites affect ecosystem structure and function. Thus, there is an urgent need to revisit how parasites are viewed from a conservation perspective and broaden the role that disease ecology plays in conservation-related research and outcomes. This review broadly focusses on the role that disease ecology can play in biological conservation. Our review specifically emphasizes on how the integration of tools and analytical approaches associated with both disease and molecular ecology can be leveraged to aid conservation biology. Our review first concentrates on disease-mediated extinctions and wildlife epidemics. We then focus on elucidating how host–parasite interactions has improved our understanding of the eco-evolutionary dynamics affecting hosts at the individual, population, community and ecosystem scales. We believe that the role of parasites as drivers and indicators of ecosystem health is especially an exciting area of research that has the potential to fundamentally alter our view of parasites and their role in biological conservation. The review concludes with a broad overview of the current and potential applications of modern genomic tools in disease ecology to aid biological conservation.

Emerging Parvoviruses in Domestic Cats

Parvovirus infections in cats have been well known for around 100 years. Recently, the use of molecular assays and metagenomic approaches for virus discovery and characterization has led to the detection of novel parvovirus lineages and/or species infecting the feline host. However, the involvement of emerging parvoviruses in the onset of gastroenteritis or other feline diseases is still uncertain.

Bat virome research: the past, the present and the future

Bats have been increasingly recognised as an exceptional reservoir for emerging zoonotic viruses for the past few decades. Recent studies indicate that the unique bat immune system may be partially responsible for their ability to co-exist with viruses with minimal or no clinical diseases. In this review, we discuss the history and importance of bat virome studies and contrast the vast difference between such studies before and after the introduction of next generation sequencing (NGS) in this area of research. We also discuss the role of discovery serology and high-throughput single cell RNA-seq in future bat virome research.

Circovirus in Blood of a Febrile Horse with Hepatitis

Circoviruses infect vertebrates where they can result in a wide range of disease signs or in asymptomatic infections. Using viral metagenomics we analyzed a pool of five sera from four healthy and one sick horse. Sequences from parvovirus-H, equus anellovirus, and distantly related to mammalian circoviruses were recognized. PCR identified the circovirus reads as originating from a pregnant mare with fever and hepatitis. That horse's serum was also positive by real time PCR for equine parvovirus H and negative for the flavivirus equine hepacivirus. The complete circular genome of equine circovirus 1 strain Charaf (EqCV1-Charaf) was completed using PCR and Sanger sequencing. EqCV1 replicase showed 73-74% identity to those of their closest relatives, pig circoviruses 1/2, and elk circovirus. The closest capsid proteins were from the same ungulate circoviruses with 62-63% identity. The overall nucleotide identity of 72% to its closest relative indicates that EqCV1 is a new species in the Circovirus genus, the first reported in genus Equus. Whether EqCV1 alone or in co-infections can result in disease and its prevalence in different equine populations will require further studies now facilitated using EqCV1's genome sequence.

The virome of German bats: comparing virus discovery approaches

Bats are known to be reservoirs of several highly pathogenic viruses. Hence, the interest in bat virus discovery has been increasing rapidly over the last decade. So far, most studies have focused on a single type of virus detection method, either PCR, virus isolation or virome sequencing. Here we present a comprehensive approach in virus discovery, using all three discovery methods on samples from the same bats. By family-specific PCR screening we found sequences of paramyxoviruses, adenoviruses, herpesviruses and one coronavirus. By cell culture we isolated a novel bat adenovirus and bat orthoreovirus. Virome sequencing revealed viral sequences of ten different virus families and orders: three bat nairoviruses, three phenuiviruses, one orbivirus, one rotavirus, one orthoreovirus, one mononegavirus, five parvoviruses, seven picornaviruses, three retroviruses, one totivirus and two thymoviruses were discovered. Of all viruses identified by family-specific PCR in the original samples, none was found by metagenomic sequencing. Vice versa, none of the viruses found by the metagenomic virome approach was detected by family-specific PCRs targeting the same family. The discrepancy of detected viruses by different detection approaches suggests that a combined approach using different detection methods is necessary for virus discovery studies.

Feline chaphamaparvovirus in cats with enteritis and upper respiratory tract disease

Feline chaphamaparvovirus (FeChPV) is a novel parvovirus, first discovered in a multi-facility feline shelter in Canada in 2019, during an outbreak of acute gastro-enteritis (AGE) in cats, and detected at high prevalence (47.0%) in faecal samples. Whether this finding was anecdotal or similar viruses are common components of feline virome is still unclear. Also, the potential impact of this virus on feline health is uncertain. Herewith, a case-control study was performed to investigate whether this novel parvovirus may play a role as enteric pathogen, screening samples collected from cats with and without AGE signs. Furthermore, we extended the research by testing archival paired oropharyngeal and ocular samples collected from cats with or without upper respiratory tract disease (URTD). FeChPV DNA was detected at high prevalence rate (36.8%, 14/38) in clinical cases, representing the most frequently identified enteric virus, followed by feline panleukopenia parvovirus (23.7%, 9/38), feline coronavirus (5.3%, 2/38), feline kobuvirus (5.3%, 2/38) and noroviruses (5.3%, 2/38). The different prevalence rates of FeChPV between the case and control group were statistically significant, suggesting a possible association of the virus with acute gastro-enteric disease. The virus was also detected at low rate in the respiratory samples of cats with (3.3%, 6/183) or without URTD (4.3%, 6/140), although there was no significant association between FeChPV and URTD. The complete VP encoding gene was determined for five viruses and the nearly full-length genome was reconstructed for three viruses, namely 313R/2019/ITA, 284R/2019/ITA and 49E/2019/ITA. In the NS1-based tree, the Italian strains clustered tightly with the two FeChPV prototypes detected in Canada, within a monophyletic cluster related to but clearly distinct from canine chaphamaparvovirus, currently classified in the species Carnivore chaphamaparvovirus 1 (CaChPV-1).

Virome of Bat Guano from Nine Northern California Roosts

Bats are hosts to a large variety of viruses, including many capable of cross-species transmissions to other mammals, including humans. We characterized the virome in guano from five common bat species in 9 Northern California roosts and from a pool of 5 individual bats. Genomes belonging to 14 viral families known to infect mammals and 17 viral families infecting insects or of unknown tropism were detected. Nearly complete or complete genomes of a novel parvovirus, astrovirus, nodavirus, circular Rep-encoding single-stranded DNA (CRESS-DNA) viruses, and densoviruses, and more partial genomes of a novel alphacoronavirus and a bunyavirus were characterized. Lower numbers of reads with >90% amino acid identity to previously described calicivirus, circovirus, adenoviruses, hepatovirus, bocaparvoviruses, and polyomavirus in other bat species were also found, likely reflecting their wide distribution among different bats. Unexpectedly, a few sequence reads of canine parvovirus 2 and the recently described mouse kidney parvovirus were also detected and their presence confirmed by PCR; these possibly originated from guano contamination by carnivores and rodents. The majority of eukaryotic viral reads were highly divergent, indicating that numerous viruses still remain to be characterized, even from such a heavily investigated order as Chiroptera.IMPORTANCE Characterizing the bat virome is important for understanding viral diversity and detecting viral spillover between animal species. Using an unbiased metagenomics method, we characterize the virome in guano collected from multiple roosts of common Northern California bat species. We describe several novel viral genomes and report the detection of viruses with close relatives reported in other bat species, likely reflecting cross-species transmissions. Viral sequences from well-known carnivore and rodent parvoviruses were also detected, whose presence are likely the result of contamination from defecation and urination atop guano and which reflect the close interaction of these mammals in the wild.

Genetic Analysis of Cachavirus-Related Parvoviruses Detected in Pet Cats: The First Report From China

In this study, members of the Carnivore chaphamaparvovirus species 1, closely related to a virus previously reported in dog feces named cachavirus was identified for the first time in feces of Chinese cats. Screening tests using rectal swabs from 171 diarrheic and 378 healthy cats collected from Henan, Anhui, and Zhejiang provinces in China revealed two samples from diarrheic cats that were positive for cachavirus, but statistical analysis indicated no association between the presence of the virus and clinical signs (p > 0.05). Subsequently, two partial genome sequences [from nucleotides 479–4123, according to the strains from dogs (cachavirus)] of the two strains from cats (cachavirus-cat1 and -cat2) were amplified. The NS1 and VP1 sites of cachavirus-cat1 and -cat2 shared a high identity of 91.9 and 97.0% with reported cachaviruses, respectively, but lower identity of 74.8 and 73.2% with another carnivore chaphamaparvovirus named fechaviruses detected in cats, respectively, indicated the two strains might origin from dogs. These findings improve our understanding of the diversity and tropism of viruses in Carnivore chaphamaparvovirus species 1 which now include both dogs and now cats viruses.

Detection and genetic characterization of a novel parvovirus (family Parvoviridae) in barn owls (Tyto alba) in Hungary

In this study, a novel parvovirus (gyb-MR02/2015/HUN, MT580795) was detected in barn owls (Tyto alba) and genetically characterized using viral metagenomics and PCR methods. The NS1 and VP1 proteins of gyb-MR02/2015/HUN share only 45.4% and 50.1% amino acid sequence identity, respectively, to the corresponding proteins of peafowl parvovirus 2 (MK988620), the closest relative. Out of 11 faecal specimens from owls (six from little owls, three from barn owls, and two from long-eared owls), two barn owl samples were positive for the novel parvovirus, which is distantly related to members of the recently established genus Chaphamaparvovirus in the subfamily Hamaparvovirinae. Systematic investigation is necessary to explore the diversity of parvoviruses.

Naturally Acquired Mouse Kidney Parvovirus Infection Produces a Persistent Interstitial Nephritis in Immunocompetent Laboratory Mice

Mouse kidney parvovirus (MKPV), also known as murine chapparvovirus (MuCPV), is an emerging, highly infectious agent that has been isolated from laboratory and wild mouse populations. In immunocompromised mice, MKPV produces severe chronic interstitial nephropathy and renal failure within 4 to 5 months of infection. However, the course of disease, severity of histologic lesions, and viral shedding are uncertain for immunocompetent mice. We evaluated MKPV infections in CD-1 and Swiss Webster mice, 2 immunocompetent stocks of mice. MKPV-positive CD-1 mice (n = 30) were identified at approximately 8 weeks of age by fecal PCR (polymerase chain reaction) and were subsequently housed individually for clinical observation and diagnostic sampling. Cage swabs, fecal pellets, urine, and blood were evaluated by PCR at 100 and 128 days following the initial positive test, which identified that 28 of 30 were persistently infected and 24 of these were viremic at 100 days. Histologic lesions associated with MKPV in CD-1 (n = 31) and Swiss mice (n = 11) included lymphoplasmacytic tubulointerstitial nephritis with tubular degeneration. Inclusion bodies were rare; however, intralesional MKPV mRNA was consistently detected via in situ hybridization within tubular epithelial cells of the renal cortex and within collecting duct lumina. In immunocompetent CD-1 mice, MKPV infection resulted in persistent shedding of virus for up to 10 months and a mild tubulointerstitial nephritis, raising concerns that this virus could produce study variations in immunocompetent models. Intranuclear inclusions were not a consistent feature of MKPV infection in immunocompetent mice.

Molecular characterization of Cachavirus firstly detected in dogs in China

Canine Cachavirus was novel parvovirus species has been firstly identified in dogs in USA and was classified within the proposed Chaphamaparvovirus genus. To investigate Cachavirus infection in dogs in China, 408 rectal swabs from healthy and diarrheic dogs obtained during 2018-2019 were screened. The rate of Cachavirus positivity was 0% and 1.55% in healthy or diarrheic dogs, respectively. However, statistical analysis suggested no association between the presence of the virus and clinical signs (p > 0.05). Nucleotide identity was 98.2%-98.9% for NS1 and 98.6%-99.1% for VP1, and amino acid identity was 97.9%-98.7% for NS1 and 98.8%-99.6% for VP1 between the five Chinese strains and Cachavirus-1A and Cachavirus-1B detected in the United States. Phylogenetic analysis also indicated that these Cachavirus strains are genetically related to Cachavirus-1A and Cachavirus-1B. This study confirms the presence of Cachavirus in pet dogs in China and provides novel findings on its molecular characteristics.

Achimota Pararubulavirus 3: A New Bat-Derived Paramyxovirus of the Genus Pararubulavirus

Bats are an important source of viral zoonoses, including paramyxoviruses. The paramyxoviral Pararubulavirus genus contains viruses mostly derived from bats that are common, diverse, distributed throughout the Old World, and known to be zoonotic. Here, we describe a new member of the genus Achimota pararubulavirus 3 (AchPV3) and its isolation from the urine of African straw-coloured fruit bats on primary bat kidneys cells. We sequenced and analysed the genome of AchPV3 relative to other Paramyxoviridae, revealing it to be similar to known pararubulaviruses. Phylogenetic analysis of AchPV3 revealed the failure of molecular detection in the urine sample from which AchPV3 was derived and an attachment protein most closely related with AchPV2—a pararubulavirus known to cause cross-species transmission. Together these findings add to the picture of pararubulaviruses, their sources, and variable zoonotic potential, which is key to our understanding of host restriction and spillover of bat-derived paramyxoviruses. AchPV3 represents a novel candidate zoonosis and an important tool for further study.

Cell Cultures for Virology: Usability, Advantages, and Prospects

Virus detection in natural and clinical samples is a complicated problem in research and diagnostics. There are different approaches for virus isolation and identification, including PCR, CRISPR/Cas technology, NGS, immunoassays, and cell-based assays. Following the development of genetic engineering methods, approaches that utilize cell cultures have become useful and informative. Molecular biology methods allow increases in the sensitivity and specificity of cell cultures for certain viruses and can be used to generate reporter cell lines. These cell lines express specific reporter proteins (e.g., GFP, luciferase, and CAT) in response to virus infection that can be detected in a laboratory setting. The development of genome editing and synthetic biology methods has given rise to new perspectives regarding the design of virus reporter systems in cell cultures. This review is aimed at describing both virology methods in general and examples of the development of cell-based methods that exist today.

Molecular detection and characterization of Carnivore chaphamaparvovirus 1 in dogs

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Canine chaphamaparvovirus (CaChPV) is a novel parvovirus recently discovered in dogs;

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Herein, stool samples from dogs with or without enteric signs were screened for CaChPV;

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CaChPV DNA was found either in diarrhoeic (1.9 %) or asymptomatic (1.6 %) dogs;

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The nearly complete genome sequences were determined for two strains;

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The Italian CaChPV strains tightly clustered with the American reference viruses.

Canine chaphamaparvovirus (CaChPV) is a newly recognised parvovirus discovered by metagenomic analysis during an outbreak of diarrhoea in dogs in Colorado, USA, in 2017 and more recently detected in diarrhoeic dogs in China. Whether the virus plays a role as canine pathogen and whether it is distributed elsewhere, in other geographical areas, is not known. We performed a case-control study to investigate the possible association of CaChPV with enteritis in dogs. CaChPV DNA was detected both in the stools of diarrhoeic dogs (1.9 %, 3/155) and of healthy animals (1.6 %, 2/120). All the CaChPV-infected dogs with diarrhea were mixed infected with other enteric viruses such as canine parvovirus (formerly CPV-2), canine bufavirus (CBuV) and canine coronavirus (CCoV), whilst none of the asymptomatic CaChPV positive animals resulted co-infected. The nearly full-length genome and the partial capsid protein (VP) gene of three canine strains, Te/36OVUD/19/ITA, Te/37OVUD/19/ITA and Te/70OVUD/19/ITA, were reconstructed. Upon phylogenetic analyses based on the NS1 and VP aa sequences, the Italian CaChPV strains tightly clustered with the American reference viruses. Distinctive residues could be mapped to the deduced variable regions of the VP of canine and feline chaphamaparvoviruses, considered as important markers of host range and pathogenicity for parvoviruses.

Metatranscriptomic Analysis of Virus Diversity in Urban Wild Birds with Paretic Disease

Wildlife naturally harbor a diverse array of infectious microorganisms and can be a source of novel diseases in domestic animals and human populations. Using unbiased RNA sequencing, we identified highly diverse viruses in native birds from Australian urban environments presenting with paresis. This research included the clinical investigation and description of poorly understood recurring syndromes of unknown etiology: clenched claw syndrome and black and white bird disease. As well as identifying a range of potentially disease-causing viral pathogens, this study describes methods that can effectively and efficiently characterize emergent disease syndromes in free-ranging wildlife and promotes further surveillance for specific pathogens of potential conservation and zoonotic concern.

Wild birds are major natural reservoirs and potential dispersers of a variety of infectious diseases. As such, it is important to determine the diversity of viruses they carry and use this information to help understand the potential risks of spillover to humans, domestic animals, and other wildlife. We investigated the potential viral causes of paresis in long-standing, but undiagnosed, disease syndromes in wild Australian birds. RNA from diseased birds was extracted and pooled based on tissue type, host species, and clinical manifestation for metagenomic sequencing. Using a bulk and unbiased metatranscriptomic approach, combined with clinical investigation and histopathology, we identified a number of novel viruses from the families Astroviridae, Adenoviridae, Picornaviridae, Polyomaviridae, Paramyxoviridae, Parvoviridae, and Circoviridae in common urban wild birds, including Australian magpies, magpie larks, pied currawongs, Australian ravens, and rainbow lorikeets. In each case, the presence of the virus was confirmed by reverse transcription (RT)-PCR. These data revealed a number of candidate viral pathogens that may contribute to coronary, skeletal muscle, vascular, and neuropathology in birds of the Corvidae and Artamidae families and neuropathology in members of the Psittaculidae. The existence of such a diverse virome in urban avian species highlights the importance and challenges in elucidating the etiology and ecology of wildlife pathogens in urban environments. This information will be increasingly important for managing disease risks and conducting surveillance for potential viral threats to wildlife, livestock, and human health.

IMPORTANCE Wildlife naturally harbor a diverse array of infectious microorganisms and can be a source of novel diseases in domestic animals and human populations. Using unbiased RNA sequencing, we identified highly diverse viruses in native birds from Australian urban environments presenting with paresis. This research included the clinical investigation and description of poorly understood recurring syndromes of unknown etiology: clenched claw syndrome and black and white bird disease. As well as identifying a range of potentially disease-causing viral pathogens, this study describes methods that can effectively and efficiently characterize emergent disease syndromes in free-ranging wildlife and promotes further surveillance for specific pathogens of potential conservation and zoonotic concern.

Characterization of a Novel Alphaherpesvirus Isolated from the Fruit Bat Pteropus lylei in Vietnam

Herpesviruses exist in nature within each host animal. Ten herpesviruses have been isolated from bats and their biological properties reported. A novel bat alphaherpesvirus, which we propose to name "Pteropus lylei-associated alphaherpesvirus (PLAHV)," was isolated from urine of the fruit bat Pteropus lylei in Vietnam and characterized. The entire genome sequence was determined to be 144,008 bp in length and predicted to include 72 genes. PLAHV was assigned to genus Simplexvirus with other bat alphaherpesviruses isolated from pteropodid bats in Southeast Asia and Africa. The replication capacity of PLAHV in several cells was evaluated in comparison with that of herpes simplex virus 1 (HSV-1). PLAHV replicated better in the bat-originated cell line and less in human embryonic lung fibroblasts than HSV-1 did. PLAHV was serologically related to another bat alphaherpesvirus, Pteropodid alphaherpesvirus 1 (PtAHV1), isolated from a Pteropus hypomelanus-related bat captured in Indonesia, but not with HSV-1. PLAHV caused lethal infection in mice. PLAHV was as susceptible to acyclovir as HSV-1 was. Characterization of this new member of bat alphaherpesviruses, PLAHV, expands the knowledge on bat-associated alphaherpesvirology.IMPORTANCE A novel bat alphaherpesvirus, Pteropus lylei-associated alphaherpesvirus (PLAHV), was isolated from urine of the fruit bat Pteropus lylei in Vietnam. The whole-genome sequence was determined and was predicted to include 72 open reading frames in the 144,008-bp genome. PLAHV is circulating in a species of fruit bats, Pteropus lylei, in Asia. This study expands the knowledge on bat-associated alphaherpesvirology.

Genomics-based re-examination of the taxonomy and phylogeny of human and simian Mastadenoviruses: an evolving whole genomes approach, revealing putative zoonosis, anthroponosis, and amphizoonosis

With the advent of high-resolution and cost-effective genomics and bioinformatics tools and methods contributing to a large database of both human (HAdV) and simian (SAdV) adenoviruses, a genomics-based re-evaluation of their taxonomy is warranted. Interest in these particular adenoviruses is growing in part due to the applications of both in gene transfer protocols, including gene therapy and vaccines, as well in oncolytic protocols. In particular, the re-evaluation of SAdVs as appropriate vectors in humans is important as zoonosis precludes the assumption that human immune system may be naïve to these vectors. Additionally, as important pathogens, adenoviruses are a model organism system for understanding viral pathogen emergence through zoonosis and anthroponosis, particularly among the primate species, along with recombination, host adaptation, and selection, as evidenced by one long-standing human respiratory pathogen HAdV-4 and a recent re-evaluation of another, HAdV-76. The latter reflects the insights on amphizoonosis, defined as infections in both directions among host species including "other than human", that are possible with the growing database of nonhuman adenovirus genomes. HAdV-76 is a recombinant that has been isolated from human, chimpanzee, and bonobo hosts. On-going and potential impacts of adenoviruses on public health and translational medicine drive this evaluation of 174 whole genome sequences from HAdVs and SAdVs archived in GenBank. The conclusion is that rather than separate HAdV and SAdV phylogenetic lineages, a single, intertwined tree is observed with all HAdVs and SAdVs forming mixed clades. Therefore, a single designation of "primate adenovirus" (PrAdV) superseding either HAdV and SAdV is proposed, or alternatively, keeping HAdV for human adenovirus but expanding the SAdV nomenclature officially to include host species identification as in ChAdV for chimpanzee adenovirus, GoAdV for gorilla adenovirus, BoAdV for bonobo adenovirus, and ad libitum.

Novel herpesviruses in neotropical bats and their relationship with other members of the Herpesviridae family

In the past decade, a large number of studies have detected herpesvirus sequences from many bat species around the world. Nevertheless, the discovery of bat herpesviruses is geographically uneven. Of the various bat species tested to date, only a few were from the New World. Seeking to investigate the distribution and diversity of herpesviruses circulating in neotropical bats, we carried out molecular screening of 195 blood DNA samples from 11 species of three bat families (Phyllostomidae, Mormoopidae, and Molossidae). Using polymerase chain reaction amplification, with degenerate consensus primers targeting highly conserved amino acid motifs of the herpesvirus DNA polymerase and Glycoprotein B genes, we characterized novel viral sequences from all tested species. BLAST searches, pairwise nucleotide and amino acid sequence comparisons, as well as phylogenetic analyses confirmed that they all belonged to the Herpesviridae family, of the Beta- and Gammaherpesvirinae subfamilies. Fourteen partial DNA polymerase gene sequences, of which three beta- and 11 gamma-herpesviruses, were detected. A total of 12 partial Glycoprotein B gene sequences, all gamma-herpesviruses, were characterized. Every sequence was specific to a bat species and in some species (Desmodus rotundus, Carollia perspicillata, and Pteronotus rubiginosus) multiple viruses were found. Phylogenetic analyses of beta- and gammaherpesvirus sequences led to the identification of bat-specific clades. Those composed of sequences obtained from different bat species belonging to distinct subfamilies follow the taxonomy of bats. This study confirms the astonishing diversity of bat herpesviruses and broadens our knowledge of their host range. Nevertheless, it also emphasizes the fact that, to better appreciate the evolutionary history of these viruses, much remains to be done at various taxonomic levels.

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Molecular screening was carried out on 11 bat species from French Guiana and Martinique (French West Indies).

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Partial DNA polymerase gene sequences of 14 viruses were characterized as well as 12 Glycoprotein B sequences.

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Genetic characterization of these sequences reveals a high degree of genetic divergence.

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Phylogenetically, most of the newly discovered sequences fall within bat-specific clades well correlated with the taxonomy of their hosts.

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This study is the largest conducted to date in terms of species diversity from the New World.

Virome of a Feline Outbreak of Diarrhea and Vomiting Includes Bocaviruses and a Novel Chapparvovirus

An unexplained outbreak of feline diarrhea and vomiting, negative for common enteric viral and bacterial pathogens, was subjected to viral metagenomics and PCR. We characterized from fecal samples the genome of a novel chapparvovirus we named fechavirus that was shed by 8/17 affected cats and identified three different feline bocaviruses shed by 9/17 cats. Also detected were nucleic acids from attenuated vaccine viruses, members of the normal feline virome, viruses found in only one or two cases, and viruses likely derived from ingested food products. Epidemiological investigation of disease signs, time of onset, and transfers of affected cats between three facilities support a possible role for this new chapparvovirus in a highly contagious feline diarrhea and vomiting disease.

A Preliminary Study of the Virome of the South American Free-Tailed Bats (Tadarida brasiliensis) and Identification of Two Novel Mammalian Viruses

Bats provide important ecosystem services as pollinators, seed dispersers, and/or insect controllers, but they have also been found harboring different viruses with zoonotic potential. Virome studies in bats distributed in Asia, Africa, Europe, and North America have increased dramatically over the past decade, whereas information on viruses infecting South American species is scarce. We explored the virome of Tadarida brasiliensis, an insectivorous New World bat species inhabiting a maternity colony in Rosario (Argentina), by a metagenomic approach. The analysis of five pooled oral/anal swab samples indicated the presence of 43 different taxonomic viral families infecting a wide range of hosts. By conventional nucleic acid detection techniques and/or bioinformatics approaches, the genomes of two novel viruses were completely covered clustering into the Papillomaviridae (Tadarida brasiliensis papillomavirus type 1, TbraPV1) and Genomoviridae (Tadarida brasiliensis gemykibivirus 1, TbGkyV1) families. TbraPV1 is the first papillomavirus type identified in this host and the prototype of a novel genus. TbGkyV1 is the first genomovirus reported in New World bats and constitutes a new species within the genus Gemykibivirus. Our findings extend the knowledge about oral/anal viromes of a South American bat species and contribute to understand the evolution and genetic diversity of the novel characterized viruses.

Plasma virome of 781 Brazilians with unexplained symptoms of arbovirus infection include a novel parvovirus and densovirus

Plasma from patients with dengue-like symptoms was collected in 2013 to 2016 from the Brazilian states of Tocantins and Amapa. 781 samples testing negative for IgM against Dengue, Zika, and Chikungunya viruses and for flaviviruses, alphaviruses and enteroviruses RNA using RT-PCRs were analyzed using viral metagenomics. Viral particles-associated nucleic acids were enriched, randomly amplified, and deep sequenced in 102 mini-pools generating over 2 billion reads. Sequence data was analyzed for the presence of known and novel eukaryotic viral reads. Anelloviruses were detected in 80%, human pegivirus 1 in 19%, and parvovirus B19 in 17% of plasma pools. HIV and enteroviruses were detected in two pools each. Previously uncharacterized viral genomes were also identified, and their presence in single plasma samples confirmed by PCR. Chapparvovirus and ambidensovirus genomes, both in the Parvoviridae family, were partially characterized showing 33% and 34% identity in their NS1 sequences to their closest relative. Molecular surveillance using pre-existing plasma from febrile patients provides a readily scalable approach for the detection of novel, potentially emerging, viruses.

A novel poxvirus isolated from an Egyptian fruit bat in Israel

An Egyptian fruit bat (Rousettus aegyptiacus) from the Zoological Gardens, at Tel Aviv, Israel, showed pox‐like clinical signs including vesicular and nodular skin lesions on the wings. Cell culture isolation, histopathology, electron microscopy and molecular analysis, revealed the presence of a novel bat poxvirus. Future research is needed to determine whether this virus can affect human health.