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Buigues J, Viñals A, Martínez-Recio R, Monrós JS, Sanjuán R, Cuevas JM. Full-genome sequencing of dozens of new DNA viruses found in Spanish bat feces. Microbiol Spectr 2024:e0067524. [PMID: 38990026 DOI: 10.1128/spectrum.00675-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2024] [Accepted: 06/26/2024] [Indexed: 07/12/2024] Open
Abstract
Bats are natural hosts of multiple viruses, many of which have clear zoonotic potential. The search for emerging viruses has been aided by the implementation of metagenomic tools, which have also enabled the detection of unprecedented viral diversity. Currently, this search is mainly focused on RNA viruses, which are largely over-represented in databases. To compensate for this research bias, we analyzed fecal samples from 189 Spanish bats belonging to 22 different species using viral metagenomics. This allowed us to identify 52 complete or near-complete viral genomes belonging to the families Adenoviridae, Circoviridae, Genomoviridae, Papillomaviridae, Parvoviridae, Polyomaviridae and Smacoviridae. Of these, 30 could constitute new species, doubling the number of viruses currently described in Europe. These findings open the door to a more thorough analysis of bat DNA viruses and their zoonotic potential. IMPORTANCE Metagenomics has become a fundamental tool to characterize the global virosphere, allowing us not only to understand the existing viral diversity and its ecological implications but also to identify new and emerging viruses. RNA viruses have a higher zoonotic potential, but this risk is also present for some DNA virus families. In our study, we analyzed the DNA fraction of fecal samples from 22 Spanish bat species, identifying 52 complete or near-complete genomes of different viral families with zoonotic potential. This doubles the number of genomes currently described in Europe. Metagenomic data often produce partial genomes that can be difficult to analyze. Our work, however, has characterized a large number of complete genomes, thus facilitating their taxonomic classification and enabling different analyses to be carried out to evaluate their zoonotic potential. For example, recombination studies are relevant since this phenomenon could play a major role in cross-species transmission.
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Affiliation(s)
- Jaime Buigues
- Institute for Integrative Systems Biology (I2SysBio), Universitat de València and Consejo Superior de Investigaciones Científicas, València, Spain
| | - Adrià Viñals
- Institut Cavanilles de Biodiversitat i Biologia Evolutiva, Universitat de València, València, Spain
| | - Raquel Martínez-Recio
- Institute for Integrative Systems Biology (I2SysBio), Universitat de València and Consejo Superior de Investigaciones Científicas, València, Spain
| | - Juan S Monrós
- Institut Cavanilles de Biodiversitat i Biologia Evolutiva, Universitat de València, València, Spain
| | - Rafael Sanjuán
- Institute for Integrative Systems Biology (I2SysBio), Universitat de València and Consejo Superior de Investigaciones Científicas, València, Spain
- Department of Genetics, Universitat de València, València, Spain
| | - José M Cuevas
- Institute for Integrative Systems Biology (I2SysBio), Universitat de València and Consejo Superior de Investigaciones Científicas, València, Spain
- Department of Genetics, Universitat de València, València, Spain
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Pu J, Zhang Y, Zhong D, Chen Q. Detection and genetic characterization of circulating canine parvovirus from stray dogs in Shanghai, China. Virology 2024; 595:110041. [PMID: 38555807 DOI: 10.1016/j.virol.2024.110041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Revised: 02/02/2024] [Accepted: 02/28/2024] [Indexed: 04/02/2024]
Abstract
Canine parvovirus (CPV) is the main cause of viral diarrhea in dogs. CPV became a global disease in 1978 and was endemic all over the world. CPV-2 was the first strain to be identified, but with genetic mutations, new genotypes such as CPV-2a/2b/2c/new-2a/new-2b have emerged. In this study, 128 fecal samples of stray dogs suspected of CPV-2 infection were collected from January to March 2021 in Shanghai, China. All samples were screened by PCR and further analyzed by VP2 gene. The positive rate of CPV-2 was 9.4% (12/128), of which 6 CPV-2 isolates were successfully isolated. Phylogenetic tree analysis showed that 4 isolates were CPV-2c genotype and 2 were new-CPV-2b genotype. VP-2 is a key protein that determines the antigenic properties, host range and receptor binding of cpv-2. The results of VP2 amino acid sequence analysis in this study showed that the CPV-2c isolated strain was the same as the previous strains reported in China, including F267Y, Y324I, Q370R and A5G mutations in addition to the typical N426E mutations. Similarly, in addition to the conventional N426D, S297A, F267Y and Y324I mutations, the new CPV-2b isolate also had a new mutation of T440A. This study further confirmed the prevalence of CPV-2c and new-CPV-2b in Shanghai, and also found a new mutation site of new-CPV-2c, which provided a theoretical basis for further enriching the epidemiological data of CPV-2 in Shanghai, as well as the development of vaccines and the prevention and control of the disease.
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Affiliation(s)
- Junyi Pu
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, PR China; SNLG Precision Medtech (Shanghai) Ltd, Shanghai, 201100, PR China
| | - Yan Zhang
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, PR China
| | - Dengke Zhong
- Shanghai Vocational and Technical College of Agriculture and Forestry, Shanghai, 201600, PR China.
| | - Qiusheng Chen
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, PR China.
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Mira F, Schirò G, Franzo G, Canuti M, Purpari G, Giudice E, Decaro N, Vicari D, Antoci F, Castronovo C, Guercio A. Molecular epidemiology of canine parvovirus type 2 in Sicily, southern Italy: A geographical island, an epidemiological continuum. Heliyon 2024; 10:e26561. [PMID: 38420403 PMCID: PMC10900816 DOI: 10.1016/j.heliyon.2024.e26561] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Revised: 02/10/2024] [Accepted: 02/15/2024] [Indexed: 03/02/2024] Open
Abstract
Since it emerged as a major dog pathogen, canine parvovirus type 2 (CPV-2) has featured a remarkable genetic and phenotypic heterogeneity, whose biological, epidemiological, and clinical impact is still debated. The continuous monitoring of this pathogen is thus of pivotal importance. In the present study, the molecular epidemiology of CPV-2 in Sicily, southern Italy, has been updated by analysing 215 nearly complete sequences of the capsid protein VP2, obtained from rectal swabs/faeces or tissue samples collected between 2019 and 2022 from 346 dogs with suspected infectious gastrointestinal disease. The presence of the original CPV-2 type (4%) and CPV-2a (9%), CPV-2b (18%), or CPV-2c (69%) variants was documented. Over the years, we observed a decrease in the frequency of CPV-2a/-2b and a rapid increase of CPV-2c frequency, with a progressive replacement of the European lineage of CPV-2c by the Asian lineage. The observed scenario, besides confirming epidemiological relevance of CPV-2, highlights the occurrence of antigenic variant shifts over time, with a trend toward the replacement of CPV-2a, CPV-2b, and the European lineage of CPV-2c by the emerging Asian CPV-2c lineage. The comparison with other Italian and international sequences suggests the occurrence of viral exchange with other Italian regions and different countries, although the directionality of such viral flows could not be often established with confidence. In several instances, potential CPV-2 introductions led to epidemiological dead ends. However, major, long-lasting clades were also identified, supporting successful infection establishment, local spreading, and evolution. These results, besides demonstrating the need for implementing more effective control measures to prevent viral introductions and minimize circulation, stress the relevance of routine monitoring activities as the only tool to effectively understand CPV-2 epidemiology and evolution, and develop adequate countermeasures.
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Affiliation(s)
- Francesco Mira
- Istituto Zooprofilattico Sperimentale della Sicilia "A. Mirri", Via Gino Marinuzzi 3, 90129, Palermo, Italy
- Department of Veterinary Science, University of Messina, Polo Universitario dell'Annunziata, 98168, Messina, Italy
| | - Giorgia Schirò
- Istituto Zooprofilattico Sperimentale della Sicilia "A. Mirri", Via Gino Marinuzzi 3, 90129, Palermo, Italy
- Department of Veterinary Science, University of Messina, Polo Universitario dell'Annunziata, 98168, Messina, Italy
| | - Giovanni Franzo
- Department of Animal Medicine, Production and Health, University of Padua, Viale dell'Università 16, 35020, Legnaro (PD), Italy
| | - Marta Canuti
- Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Via Francesco Sforza 35, 20122, Milan, Italy
- Coordinate Research Centre EpiSoMI (Epidemiology and Molecular Surveillance of Infections), Università degli Studi di Milano, Milan, Italy
- Centre for Multidisciplinary Research in Health Science (MACH), Università degli Studi di Milano, Milan, Italy
| | - Giuseppa Purpari
- Istituto Zooprofilattico Sperimentale della Sicilia "A. Mirri", Via Gino Marinuzzi 3, 90129, Palermo, Italy
| | - Elisabetta Giudice
- Department of Veterinary Science, University of Messina, Polo Universitario dell'Annunziata, 98168, Messina, Italy
| | - Nicola Decaro
- Department of Veterinary Medicine, University of Bari Aldo Moro, S.p. per Casamassima Km 3, 70010, Valenzano, (BA), Italy
| | - Domenico Vicari
- Istituto Zooprofilattico Sperimentale della Sicilia "A. Mirri", Via Gino Marinuzzi 3, 90129, Palermo, Italy
| | - Francesco Antoci
- Istituto Zooprofilattico Sperimentale della Sicilia "A. Mirri", Via Gino Marinuzzi 3, 90129, Palermo, Italy
| | - Calogero Castronovo
- Istituto Zooprofilattico Sperimentale della Sicilia "A. Mirri", Via Gino Marinuzzi 3, 90129, Palermo, Italy
| | - Annalisa Guercio
- Istituto Zooprofilattico Sperimentale della Sicilia "A. Mirri", Via Gino Marinuzzi 3, 90129, Palermo, Italy
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Franzo G, Mira F, Schirò G, Canuti M. Not Asian Anymore: Reconstruction of the History, Evolution, and Dispersal of the "Asian" Lineage of CPV-2c. Viruses 2023; 15:1962. [PMID: 37766368 PMCID: PMC10535194 DOI: 10.3390/v15091962] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Revised: 09/14/2023] [Accepted: 09/18/2023] [Indexed: 09/29/2023] Open
Abstract
Variability has been one of the hallmarks of canine parvovirus type 2 (CPV-2) since its discovery, and several lineages and antigenic variants have emerged. Among these, a group of viruses commonly called Asian CPV-2c has recently been reported with increasing frequency in different regions. Currently, its global epidemiology and evolution are essentially unknown. The present work deals with this information gap by evaluating, via sequence, phylodynamic, and phylogeographic analyses, all the complete coding sequences of strains classified as Asian CPV-2c based on a combination of amino acid markers and phylogenetic analysis. After its estimated origin around 2008, this lineage circulated undetected in Asia until approximately 2012, when an expansion in viral population size and geographical distribution occurred, involving Africa, Europe, and North America. Asia was predicted to be the main nucleus of viral dispersal, leading to multiple introduction events in other continents/countries, where infection establishment, persistence, and rapid evolution occurred. Although the dog is the main host, other non-canine species were also involved, demonstrating the host plasticity of this lineage. Finally, although most of the strains showed an amino acid motif considered characteristic of this lineage, several exceptions were observed, potentially due to convergent evolution or reversion phenomena.
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Affiliation(s)
- Giovanni Franzo
- Department of Animal Medicine, Production and Health (MAPS), Padua University, 35020 Legnaro, Italy
| | - Francesco Mira
- Istituto Zooprofilattico Sperimentale della Sicilia “A. Mirri”, 90129 Palermo, Italy; (F.M.); (G.S.)
- Department of Veterinary Science, University of Messina, Polo Universitario dell’Annunziata, 98168 Messina, Italy
| | - Giorgia Schirò
- Istituto Zooprofilattico Sperimentale della Sicilia “A. Mirri”, 90129 Palermo, Italy; (F.M.); (G.S.)
- Department of Veterinary Science, University of Messina, Polo Universitario dell’Annunziata, 98168 Messina, Italy
| | - Marta Canuti
- Department of Pathophysiology and Transplantation, Università degli Studi di Milano, 20122 Milan, Italy
- Coordinate Research Centre EpiSoMI (Epidemiology and Molecular Surveillance of Infections), Università degli Studi di Milano, 20122 Milan, Italy
- Centre for Multidisciplinary Research in Health Science (MACH), Università degli Studi di Milano, 20122 Milan, Italy
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Viral Metagenomic Analysis of the Fecal Samples in Domestic Dogs (Canis lupus familiaris). Viruses 2023; 15:v15030685. [PMID: 36992396 PMCID: PMC10058366 DOI: 10.3390/v15030685] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Revised: 02/24/2023] [Accepted: 03/02/2023] [Indexed: 03/08/2023] Open
Abstract
Canine diarrhea is a common intestinal illness that is usually caused by viruses, bacteria, and parasites, and canine diarrhea may induce morbidity and mortality of domestic dogs if treated improperly. Recently, viral metagenomics was applied to investigate the signatures of the enteric virome in mammals. In this research, the characteristics of the gut virome in healthy dogs and dogs with diarrhea were analyzed and compared using viral metagenomics. The alpha diversity analysis indicated that the richness and diversity of the gut virome in the dogs with diarrhea were much higher than the healthy dogs, while the beta diversity analysis revealed that the gut virome of the two groups was quite different. At the family level, the predominant viruses in the canine gut virome were certified to be Microviridae, Parvoviridae, Siphoviridae, Inoviridae, Podoviridae, Myoviridae, and others. At the genus level, the predominant viruses in the canine gut virome were certified to be Protoparvovirus, Inovirus, Chlamydiamicrovirus, Lambdavirus, Dependoparvovirus, Lightbulbvirus, Kostyavirus, Punavirus, Lederbergvirus, Fibrovirus, Peduovirus, and others. However, the viral communities between the two groups differed significantly. The unique viral taxa identified in the healthy dogs group were Chlamydiamicrovirus and Lightbulbvirus, while the unique viral taxa identified in the dogs with diarrhea group were Inovirus, Protoparvovirus, Lambdavirus, Dependoparvovirus, Kostyavirus, Punavirus, and other viruses. Phylogenetic analysis based on the near-complete genome sequences showed that the CPV strains collected in this study together with other CPV Chinese isolates clustered into a separate branch, while the identified CAV-2 strain D5-8081 and AAV-5 strain AAV-D5 were both the first near-complete genome sequences in China. Moreover, the predicted bacterial hosts of phages were certified to be Campylobacter, Escherichia, Salmonella, Pseudomonas, Acinetobacter, Moraxella, Mediterraneibacter, and other commensal microbiota. In conclusion, the enteric virome of the healthy dogs group and the dogs with diarrhea group was investigated and compared using viral metagenomics, and the viral communities might influence canine health and disease by interacting with the commensal gut microbiome.
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Tracing the Genetic Evolution of Canine Parvovirus Type 2 (CPV-2) in Thailand. Pathogens 2022; 11:pathogens11121460. [PMID: 36558793 PMCID: PMC9781796 DOI: 10.3390/pathogens11121460] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Revised: 11/28/2022] [Accepted: 11/29/2022] [Indexed: 12/05/2022] Open
Abstract
Canine parvovirus type 2 (CPV-2) is responsible for hemorrhagic gastroenteritis in dogs worldwide. High genomic substitution rates in CPV-2 contribute to the progressive emergence of novel variants with increased ability to evade the host immune response. Three studies have analyzed the genomic mutations of CPV-2 variants in Thailand. These investigations were independently conducted at different timepoints. Thus, a retrospective integrated analysis of CPV-2 genomic mutations has not been fully performed. Our study aimed at evaluating the evolutionary changes in CPV-2 in Thailand from 2003 to 2019. Two hundred and sixty-eight Thai CPV-2 nucleotide sequences were used for multiple amino acid sequence alignment and phylogenetic analyses. From 2003 to 2010, CPV-2a and -2b were the only variants detected. CPV-2c, emerged in 2014, replacing CPV-2a and -2b, and has become a major variant in 2019. Phylogenetic analysis revealed that the proposed mutation pattern of VP2 amino acid residues could help distinguish Thai CPV-2 variants. This comprehensive examination provides insight into the genomic evolution of CPV-2 in Thailand since its first reporting in 2003, which may facilitate the surveillance of the potential genetic alteration of emergent CPV-2 variants.
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Leopardi S, Milani A, Cocchi M, Bregoli M, Schivo A, Leardini S, Festa F, Pastori A, de Zan G, Gobbo F, Beato MS, Palei M, Bremini A, Rossmann MC, Zucca P, Monne I, De Benedictis P. Carnivore protoparvovirus 1 (CPV-2 and FPV) Circulating in Wild Carnivores and in Puppies Illegally Imported into North-Eastern Italy. Viruses 2022; 14:v14122612. [PMID: 36560617 PMCID: PMC9788561 DOI: 10.3390/v14122612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 11/18/2022] [Accepted: 11/22/2022] [Indexed: 11/25/2022] Open
Abstract
The illegal trade of animals poses several health issues to the global community, among which are the underestimated risk for spillover infection and the potential for an epizootic in both wildlife and domestic naïve populations. We herein describe the genetic and antigenic characterization of viruses of the specie Carnivore protoparvovirus 1 detected at high prevalence in puppies illegally introduced in North Eastern Italy and compared them with those circulating in wild carnivores from the same area. We found evidence of a wide diversity of canine parvoviruses (CPV-2) belonging to different antigenic types in illegally imported pups. In wildlife, we found a high circulation of feline parvovirus (FPV) in golden jackals and badgers, whereas CPV-2 was observed in one wolf only. Although supporting a possible spillover event, the low representation of wolf samples in the present study prevented us from inferring the origin, prevalence and viral diversity of the viruses circulating in this species. Therefore, we suggest performing more thorough investigations before excluding endemic CPV-2 circulation in this species.
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Affiliation(s)
- Stefania Leopardi
- National Reference Centre/WOAH Collaborating Centre for Diseases at the Animal-Human Interface, Istituto Zooprofilattico Sperimentale Delle Venezie, 35020 Legnaro, Italy
| | - Adelaide Milani
- National Reference Centre/WOAH Collaborating Centre for Diseases at the Animal-Human Interface, Istituto Zooprofilattico Sperimentale Delle Venezie, 35020 Legnaro, Italy
| | - Monia Cocchi
- Istituto Zooprofilattico Sperimentale Delle Venezie, Sezione Territoriale di Udine, 33030 Basaldella di Campoformido, Italy
| | - Marco Bregoli
- Istituto Zooprofilattico Sperimentale Delle Venezie, Sezione Territoriale di Udine, 33030 Basaldella di Campoformido, Italy
| | - Alessia Schivo
- National Reference Centre/WOAH Collaborating Centre for Diseases at the Animal-Human Interface, Istituto Zooprofilattico Sperimentale Delle Venezie, 35020 Legnaro, Italy
| | - Sofia Leardini
- National Reference Centre/WOAH Collaborating Centre for Diseases at the Animal-Human Interface, Istituto Zooprofilattico Sperimentale Delle Venezie, 35020 Legnaro, Italy
| | - Francesca Festa
- National Reference Centre/WOAH Collaborating Centre for Diseases at the Animal-Human Interface, Istituto Zooprofilattico Sperimentale Delle Venezie, 35020 Legnaro, Italy
| | - Ambra Pastori
- National Reference Centre/WOAH Collaborating Centre for Diseases at the Animal-Human Interface, Istituto Zooprofilattico Sperimentale Delle Venezie, 35020 Legnaro, Italy
| | - Gabrita de Zan
- Istituto Zooprofilattico Sperimentale Delle Venezie, Sezione Territoriale di Udine, 33030 Basaldella di Campoformido, Italy
| | - Federica Gobbo
- National Reference Centre/WOAH Collaborating Centre for Diseases at the Animal-Human Interface, Istituto Zooprofilattico Sperimentale Delle Venezie, 35020 Legnaro, Italy
| | - Maria Serena Beato
- National Reference Centre/WOAH Collaborating Centre for Diseases at the Animal-Human Interface, Istituto Zooprofilattico Sperimentale Delle Venezie, 35020 Legnaro, Italy
| | - Manlio Palei
- Central Directorate for Health, Social Policies and Disabilities, Friuli Venezia Giulia Region, 34123 Trieste, Italy
| | - Alessandro Bremini
- Central Directorate for Health, Social Policies and Disabilities, Friuli Venezia Giulia Region, 34123 Trieste, Italy
- Biocrime Veterinary Medical Intelligence Centre, c/o International Police and Custom Cooperation Centre, Thörl-Maglern, 9602 Arnoldstein, Austria
| | - Marie-Christin Rossmann
- Biocrime Veterinary Medical Intelligence Centre, c/o International Police and Custom Cooperation Centre, Thörl-Maglern, 9602 Arnoldstein, Austria
- Agiculture, Forestry, Rural Areas Veterinary Department, Land Carinthia, 9020 Klagenfurt, Austria
| | - Paolo Zucca
- Central Directorate for Health, Social Policies and Disabilities, Friuli Venezia Giulia Region, 34123 Trieste, Italy
- Biocrime Veterinary Medical Intelligence Centre, c/o International Police and Custom Cooperation Centre, Thörl-Maglern, 9602 Arnoldstein, Austria
| | - Isabella Monne
- National Reference Centre/WOAH Collaborating Centre for Diseases at the Animal-Human Interface, Istituto Zooprofilattico Sperimentale Delle Venezie, 35020 Legnaro, Italy
| | - Paola De Benedictis
- National Reference Centre/WOAH Collaborating Centre for Diseases at the Animal-Human Interface, Istituto Zooprofilattico Sperimentale Delle Venezie, 35020 Legnaro, Italy
- Correspondence:
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Identification and Molecular Characterization of a Divergent Asian-like Canine Parvovirus Type 2b (CPV-2b) Strain in Southern Italy. Int J Mol Sci 2022; 23:ijms231911240. [PMID: 36232542 PMCID: PMC9570342 DOI: 10.3390/ijms231911240] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Revised: 09/15/2022] [Accepted: 09/20/2022] [Indexed: 11/17/2022] Open
Abstract
Canine parvovirus type 2 (CPV-2) is an infectious agent relevant to domestic and wild carnivorans. Recent studies documented the introduction and spread of CPV-2c strains of Asian origin in the Italian canine population. We investigated tissue samples from a puppy collected during necropsy for the presence of viral enteropathogens and all samples tested positive only for CPV-2. The full coding sequence of a CPV-2b (VP2 426Asp) strain was obtained. This virus was related to CPV-2c strains of Asian origin and unrelated to European CPV-2b strains. The sequence had genetic signatures typical of Asian strains (NS1: 60Val, 545Val, 630Pro; VP2: 5Gly, 267Tyr, 324Ile) and mutations rarely reported in Asian CPV-2b strains (NS1: 588N; VP2: 370Arg). Phylogenetic analyses placed this strain in well-supported clades, including Asian CPV-2c-like strains, but always as a basal, single-sequence long branch. No recombination was observed for this strain, and we speculate that it could have originated from an Asian CPV-2c-like strain that acquired the 426Asp mutation. This study reports the first evidence of an Asian-like CPV-2b strain in Italy, confirming the occurrence of continuous changes in the global CPV-2 spread. Since positive convergent mutations complicate data interpretation, a combination of phylogenetic and mutation pattern analyses is crucial in studying the origin and evolution of CPV-2 strains.
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