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Xu H, Gong B, Sun Q, Li C, Zhao J, Xiang L, Li W, Guo Z, Tang YD, Leng C, Li Z, Wang Q, Zhou G, An T, Cai X, Tian ZJ, Peng J, Zhang H. Genomic Characterization and Pathogenicity of BJEU06-1-Like PRRSV-1 ZD-1 Isolated in China. Transbound Emerg Dis 2023. [DOI: 10.1155/2023/6793604] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/29/2023]
Abstract
Porcine reproductive and respiratory syndrome virus (PRRSV)-1 and PRRSV-2 have long been cocirculating in China. To date, all PRRSV-1 strains in China have been classified as subtype 1. We investigated the prevalence of PRRSV-1 in several areas of China from 2016 to 2022 and found that BJEU06-1-like strains comprised the main epidemic branch of PRRSV-1. Pathogenicity data for this subgroup are currently lacking. In this study, the Chinese BJEU06-1-like PRRSV-1 strain ZD-1 was isolated from primary alveolar macrophages (PAMs). ZD-1 has undergone no recombination and has a 5-aa discontinuous deletion in the Nsp2 protein, similar to other BJEU06-1-like strains; additionally, ZD-1 has a 26 aa C-terminal truncation in the GP3 gene. Pathogenicity studies revealed that ZD-1 causes obvious clinical symptoms: prolonged fever; reduced body weight; alveolar epithelial proliferation and moderate alveolar diaphragm widening in the lungs; diffuse lymphocytic hyperplasia in the lymph nodes; high levels of viremia in the serum; and elevated viral loads in the lungs, lymph nodes, and tonsils. These results suggested that the BJEU06-1-like PRRSV-1 strain ZD-1 is moderately pathogenic to piglets. This is the first study to evaluate the pathogenicity of the BJEU06-1-like branch in China, enriching the understanding of PRRSV-1 in China.
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Cui XY, Xia DS, Huang XY, Tian XX, Wang T, Yang YB, Wang G, Wang HW, Sun Y, Xiao YH, Tian ZJ, Cai XH, An TQ. Recombinant characteristics, pathogenicity, and viral shedding of a novel PRRSV variant derived from twice inter-lineage recombination. Vet Microbiol 2022; 271:109476. [DOI: 10.1016/j.vetmic.2022.109476] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Revised: 05/25/2022] [Accepted: 05/28/2022] [Indexed: 10/18/2022]
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Guo J, Liu Z, Tong X, Wang Z, Xu S, Chen Q, Zhou J, Fang L, Wang D, Xiao S. Evolutionary Dynamics of Type 2 Porcine Reproductive and Respiratory Syndrome Virus by Whole-Genome Analysis. Viruses 2021; 13:v13122469. [PMID: 34960738 PMCID: PMC8706008 DOI: 10.3390/v13122469] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 12/02/2021] [Accepted: 12/06/2021] [Indexed: 02/04/2023] Open
Abstract
Porcine reproductive and respiratory syndrome virus (PRRSV), an important pathogen in the swine industry, is a genetically highly diverse RNA virus. However, the phylogenetic and genomic recombination properties of this virus are not yet fully understood. In this study, we performed an integrated analysis of all available whole-genome sequences of type 2 PRRSV (n = 901) to reveal its evolutionary dynamics. The results showed that there were three distinct phylogenetic lineages of PRRSV in their distribution patterns. We identified that sublineage 2.7 (L2.7), associated with a NADC30 cluster, had the highest substitution rate and higher viral genetic diversity, and inter-lineage recombination is observed more frequently in L2.7 PRRSV compared to other sublineages. Most inter-lineage recombination events detected are observed between L2.7 PRRSVs (as major parents) and L3.4 (a JXA1-R-related cluster)/L3.7 (a WUH3-related cluster) PRRSVs (as minor parents). Moreover, the recombination hotspots are located in the structural protein gene ORF2 and ORF4, or in the non-structural protein gene nsp7. In addition, a GM2-related cluster, L3.2, shows inconsistent recombination modes compared to those of L2.7, suggesting that it may have undergone extensive and unique recombination in their evolutionary history. We also identified several amino acids under positive selection in GP2, GP4 and GP5, the major glycoproteins of PRRSV, showing the driving force behind adaptive evolution. Taken together, our results provide new insights into the evolutionary dynamics of PPRSV that contribute to our understanding of the critical factors involved in its evolution and guide future efforts to develop effective preventive measures against PRRSV.
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Affiliation(s)
- Jiahui Guo
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (J.G.); (Z.L.); (X.T.); (Z.W.); (S.X.); (Q.C.); (J.Z.); (L.F.); (S.X.)
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China
| | - Zimin Liu
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (J.G.); (Z.L.); (X.T.); (Z.W.); (S.X.); (Q.C.); (J.Z.); (L.F.); (S.X.)
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China
| | - Xue Tong
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (J.G.); (Z.L.); (X.T.); (Z.W.); (S.X.); (Q.C.); (J.Z.); (L.F.); (S.X.)
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China
| | - Zixin Wang
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (J.G.); (Z.L.); (X.T.); (Z.W.); (S.X.); (Q.C.); (J.Z.); (L.F.); (S.X.)
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China
| | - Shangen Xu
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (J.G.); (Z.L.); (X.T.); (Z.W.); (S.X.); (Q.C.); (J.Z.); (L.F.); (S.X.)
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China
| | - Qian Chen
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (J.G.); (Z.L.); (X.T.); (Z.W.); (S.X.); (Q.C.); (J.Z.); (L.F.); (S.X.)
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China
| | - Junwei Zhou
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (J.G.); (Z.L.); (X.T.); (Z.W.); (S.X.); (Q.C.); (J.Z.); (L.F.); (S.X.)
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China
| | - Liurong Fang
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (J.G.); (Z.L.); (X.T.); (Z.W.); (S.X.); (Q.C.); (J.Z.); (L.F.); (S.X.)
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China
| | - Dang Wang
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (J.G.); (Z.L.); (X.T.); (Z.W.); (S.X.); (Q.C.); (J.Z.); (L.F.); (S.X.)
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China
- Correspondence: or ; Tel.: +86-27-8728-6884; Fax: +86-27-8728-2608
| | - Shaobo Xiao
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China; (J.G.); (Z.L.); (X.T.); (Z.W.); (S.X.); (Q.C.); (J.Z.); (L.F.); (S.X.)
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan 430070, China
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A strain of highly pathogenic porcine reproductive and respiratory syndrome virus: genomic characterization, pathogenicity, and construction of an infectious full-length cDNA clone. Arch Virol 2021; 166:3127-3141. [PMID: 34529151 DOI: 10.1007/s00705-021-05212-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Accepted: 07/08/2021] [Indexed: 10/20/2022]
Abstract
Porcine reproductive and respiratory syndrome (PRRS) is a highly contagious infectious disease caused by porcine reproductive and respiratory syndrome virus (PRRSV), which inflicts major economic losses on the global pig farming industry. Based on its similarity to highly pathogenic strains, the GDzj strain isolated in this study was predicted to be highly pathogenic. We therefore analyzed the pathogenicity of this strain experimentally in piglets. All piglets challenged with this virus experienced fever or high fever, loss of appetite, decreased food intake, daily weight loss, shortness of breath, and listlessness, and the necropsy results showed that they had experienced severe interstitial pneumonia. We then used the BAC system to construct a full-length cDNA infectious clone of GDzj, and the rescued virus displayed in vitro proliferation characteristics similar to those of the parental PRRSV strain. In summary, we successfully isolated a highly pathogenic PRRSV strain and constructed a full-length infectious cDNA clone from it, thereby providing an effective reverse genetics platform for further study of viral pathogenesis.
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Jiang Y, Li X, Yu L, Tong W, Chen P, Wang S, Zhao K, Tan X, Gao F, Yu H, Li G, Li L, Zhang Y, van den Born E, Zhou Y, Tong G. Immune efficacy of a candidate porcine reproductive and respiratory syndrome vaccine rHN-NP49 administered by a Needle-free intradermal delivery system in comparison with intramuscular injection. Vaccine 2021; 39:5557-5562. [PMID: 34412921 DOI: 10.1016/j.vaccine.2021.08.023] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 08/04/2021] [Accepted: 08/08/2021] [Indexed: 11/25/2022]
Abstract
Porcine reproductive and respiratory syndrome (PRRS) is one of the major drivers of economic loss in the swine industry worldwide. In commercial pig production, vaccination is the first option in an attempt to control infectious diseases. Pigs are therefore often immunized with different vaccines, and almost all of them are delivered via the intramuscular (IM) route. However, the IM injection may result in physical damage, stress reactions, and is labor demanding. An alternative route is urgently needed to reduce the disadvantages of conventional vaccination. In this study, a needle-free intradermal (ID) delivery system was evaluated for delivering a live PRRS vaccine as compared with the traditional needle-syringe method. Fifty-two 4-week-old piglets were divided into six groups: piglets in groups A-C were immunized using ID delivery system with 104, 105 and 106 TCID50 of PRRS candidate vaccine strain rHN-NP49, respectively; piglets in group D were immunized IM with 105 TCID50 of rHN-NP49; and group E and F were used as challenge and control groups, respectively. At 28 days post vaccination, piglets in group A to E were challenged with a lethal dose of highly-pathogenic PRRSV. Similar results were found in viremia and antibody response among the ID and IM groups during the immunization stage. After challenge, similar results were found in average body weight gain, viral shedding, serum viral load, and clinical score among the immunization groups, with a higher protection ratio in the ID group compared with IM group with the same immunization dose. These results demonstrated that the ID delivery system could provide similar or even better protection compared with IM route, and could be an effective route for PRRS vaccination.
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Affiliation(s)
- Yifeng Jiang
- Department of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, PR China
| | - Xianbin Li
- Department of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, PR China
| | - Lingxue Yu
- Department of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, PR China
| | - Wu Tong
- Department of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, PR China
| | - Pengfei Chen
- Department of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, PR China
| | - Shuaiyong Wang
- Department of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, PR China
| | - Kuan Zhao
- Department of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, PR China
| | - Xiangmei Tan
- Department of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, PR China
| | - Fei Gao
- Department of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, PR China
| | - Hai Yu
- Department of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, PR China
| | - Guoxin Li
- Department of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, PR China
| | - Liwei Li
- Department of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, PR China
| | - Yujiao Zhang
- Department of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, PR China
| | | | - Yanjun Zhou
- Department of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, PR China.
| | - Guangzhi Tong
- Department of Swine Infectious Diseases, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, PR China; Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Disease and Zoonosis Yangzhou University, Yangzhou 225009, PR China.
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Zhao J, Zhu L, Deng H, Li F, Xu L, Sun X, Yin W, Kuang S, Li S, Zhou Y, Xu Z. Genetic characterization of a novel porcine reproductive and respiratory syndrome virus type I strain from southwest China. Arch Virol 2021; 166:1769-1773. [PMID: 33761009 DOI: 10.1007/s00705-021-04998-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Accepted: 12/26/2020] [Indexed: 10/21/2022]
Abstract
Porcine reproductive and respiratory syndrome (PRRS) is one of the most economically devastating viral diseases in the global pig industry. Recently, we isolated and plaque-purified porcine reproductive and respiratory syndrome virus (PRRSV) strain SC2020-1 from "aborted piglets" on a farm in Sichuan, China. To investigate the molecular biological characteristics of this strain, it was subjected to genome sequencing and analysis. The full-length genome sequence of strain SC2020-1 was 87.7% identical to that of the Lelystad strain (PRRSV type I protoype strain) and 82.2-84.8% identical to PRRSV type I isolates from China. NSP2, ORF3, and ORF4 were the most variable regions and contained discontinuous deletions or insertions when compared to other PRRSV type I strains. Phylogenetic analysis of the complete genome sequence showed that SC2020-1 clustered with PRRSV type I but outside of the three previously described branches (Lelystad virus-like, Amervac PRRS-like, and BJEU06-1-like). The Nsp2 gene was in the same branch with EUGDHD strains from China. This is the first report of PRRSV type I infection associated with abortion in sows in southwest China. Close attention should be paid to the prevention and control of this evolving virus.
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Affiliation(s)
- Jun Zhao
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Ling Zhu
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China.,Key , Laboratory of Animal Diseases and Human Health of Sichuan Province, Chengdu, China
| | - Huidan Deng
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Fengqing Li
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Lei Xu
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Xiangang Sun
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China
| | - Wenqi Yin
- Animal Breeding and Genetics Key Laboratory of Sichuan Province, Sichuan Animal Science Academy, Chengdu, China
| | - Shengyao Kuang
- Animal Breeding and Genetics Key Laboratory of Sichuan Province, Sichuan Animal Science Academy, Chengdu, China
| | | | - Yuancheng Zhou
- Animal Breeding and Genetics Key Laboratory of Sichuan Province, Sichuan Animal Science Academy, Chengdu, China. .,Livestock and Poultry Biological Products Key Laboratory of Sichuan Province, Sichuan Animal Science Academy, Chengdu, China. .,Livestock and Poultry Biological Products Key Laboratory of Sichuan Province, Animtech Bioengineering Co. Ltd, Chengdu, China.
| | - Zhiwen Xu
- College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, China. .,Key , Laboratory of Animal Diseases and Human Health of Sichuan Province, Chengdu, China.
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Jiang Y, Li G, Yu L, Li L, Zhang Y, Zhou Y, Tong W, Liu C, Gao F, Tong G. Genetic Diversity of Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) From 1996 to 2017 in China. Front Microbiol 2020; 11:618. [PMID: 32390968 PMCID: PMC7193098 DOI: 10.3389/fmicb.2020.00618] [Citation(s) in RCA: 55] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Accepted: 03/19/2020] [Indexed: 11/13/2022] Open
Abstract
Porcine reproductive and respiratory syndrome (PRRS) is one of the most devastating diseases of the global swine industry. The causative agent porcine reproductive and respiratory syndrome virus (PRRSV) was first isolated in China in 1996 and has evolved quickly during the last two decades. To fully understand virus diversity, epidemic situation in the field, and make future predictions, a total of 365 PRRSV strains were used for evolution and genome analysis in which 353 strains were isolated from mainland China. The results showed that high diversity was found among PRRSV isolates. Total PRRSV isolates could be divided into eight subgroups. Among these subgroups strains, Original HP-PRRSV, NADC30-like, and Intermediate PRRSV were the major epidemic PRRSV strains circling in the field and would play a major role in PRRS epidemic in the future. Deletions, insertions, and recombinations have occurred frequently in the PRRSV genome. Deletions were the main driving force of viral evolution before 2006 and may also contribute further to the virus' evolution in a relatively closed or low strain diversity circumstance. The recombinant strains could be divided into three groups: the Inner group, Extensional group, and Propagating group. The evolutionary directions of the isolates in the Extensional and Propagating groups have changed, and the routes of recombination in the Propagating group were analyzed and sorted into three types. The increases in recombinant strains and high rates of recombination in recent years indicate that recombination has played a very important role in the virus' evolution. Isolates, which incorporate the advantages of their parental strains, will influence PRRSV evolution and make adverse effects on PRRS control in the future.
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Affiliation(s)
- Yifeng Jiang
- Research Team on Porcine Viral Reproductive Disorder Syndrome, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, China
| | - Guoxin Li
- Research Team on Porcine Viral Reproductive Disorder Syndrome, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, China
| | - Lingxue Yu
- Research Team on Porcine Viral Reproductive Disorder Syndrome, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, China
| | - Liwei Li
- Research Team on Porcine Viral Reproductive Disorder Syndrome, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, China
| | - Yujiao Zhang
- Research Team on Porcine Viral Reproductive Disorder Syndrome, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, China
| | - Yanjun Zhou
- Research Team on Porcine Viral Reproductive Disorder Syndrome, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, China
| | - Wu Tong
- Research Team on Porcine Viral Reproductive Disorder Syndrome, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, China
| | - Changlong Liu
- Research Team on Porcine Viral Reproductive Disorder Syndrome, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, China
| | - Fei Gao
- Research Team on Porcine Viral Reproductive Disorder Syndrome, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, China
| | - Guangzhi Tong
- Research Team on Porcine Viral Reproductive Disorder Syndrome, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, China
- Jiangsu Co-innovation Center for the Prevention and Control of Important Animal Infectious Disease and Zoonosis, Yangzhou University, Yangzhou, China
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Characterization of porcine reproductive and respiratory syndrome virus (ORF5 RFLP 1-7-4 viruses) in northern China. Microb Pathog 2019; 140:103941. [PMID: 31862391 DOI: 10.1016/j.micpath.2019.103941] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2019] [Revised: 12/11/2019] [Accepted: 12/16/2019] [Indexed: 01/09/2023]
Abstract
The porcine reproductive and respiratory syndrome virus (PRRSV) is the causative agent of porcine reproductive and respiratory syndrome (PRRS). Disease outbreaks caused by NADC30-like PRRSV strains were a bit prevalent in China in recent years. In the present study, two newly emerged PRRSV strains, which were designated as PRRSV-ZDXYL-China-2018-1 and PRRSV-ZDXYL-China-2018-2 strains were found from piglets' lung tissues in Northern China. The virus belongs to lineage 1 of the PRRSV genotype 2 and is closely related to US strains that possess the open reading frame (ORF5) restriction fragment length polymorphism (RFLP) 1-7-4. The two strains were identified from infected weaning piglet herds in Zhaodong City, Heilongjiang province of China. The complete genome of the PRRSV-ZDXYL-China-2018-1 and PRRSV-ZDXYL-China-2018-2 strains were 15093 nt and 15110 nt, and shared 96.7%-97.0% and 97.1%-97.4% similarities with the US identified, ISU10 and NADC34 strains respectively. Then the PRRSV-ZDXYL-China-2018-1 strain was successfully isolated from the clinical sample. Our results demonstrate, that the emergence of ORF5 RFLP 1-7-4-like PRRSVs in China, could pose a significant challenge to PRRSV epidemic prevention.
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Zhou L, Kang R, Zhang Y, Ding M, Xie B, Tian Y, Wu X, Zuo L, Yang X, Wang H. Whole Genome Analysis of Two Novel Type 2 Porcine Reproductive and Respiratory Syndrome Viruses with Complex Genome Recombination between Lineage 8, 3, and 1 Strains Identified in Southwestern China. Viruses 2018; 10:v10060328. [PMID: 29914134 PMCID: PMC6024730 DOI: 10.3390/v10060328] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Revised: 06/09/2018] [Accepted: 06/10/2018] [Indexed: 11/16/2022] Open
Abstract
Recombination among porcine reproductive and respiratory syndrome viruses (PRRSVs) is thought to contribute to the emergence of new PRRSV variants. In this study, two newly emerged PRRSV strains, designated SCcd16 and SCya17, are isolated from lung tissues of piglets in Southwestern China. Genome comparative analysis reveals that SCcd16/SCya17 exhibit 93.1%/93.2%, 86.9%/87.0%, 85.3%/85.7%, and 83.6%/82.0% nucleotide similarity to PRRSVs JXA1, VR-2332, QYYZ and NADC30, respectively. They only exhibit 44.8%/45.1% sequence identity with LV (PRRSV-1), indicating that both emergent strains belong to the PRRSV-2 genotype. Genomic sequence alignment shows that SCcd16 and SCya17 have the same discontinuous 30-amino acid (aa) deletion in Nsp2 of the highly pathogenic Chinese PRRSV strain JXA1, when compared to strain VR-2332. Notably, SCya17 shows a unique 5-nt deletion in its 3’-UTR. Phylogenetic analysis shows that both of the isolates are classified in the QYYZ-like lineage based on ORF5 genotyping, whereas they appear to constitute an inter-lineage between JXA1-like and QYYZ-like lineages based on their genomic sequences. Furthermore, recombination analyses reveal that the two newly emerged PRRSV isolates share the same novel recombination pattern. They have both likely originated from multiple recombination events between lineage 8 (JXA1-like), lineage 1 (NADC30-like), and lineage 3 (QYYZ-like) strains that have circulated in China recently. The genomic data from SCcd16 and SCya17 indicate that there is on going evolution of PRRSV field strains through genetic recombination, leading to outbreaks in the pig populations in Southwestern China.
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Affiliation(s)
- Long Zhou
- School of Life Science, Sichuan University, Animal Disease Prevention and Food Safety Key Laboratory of Sichuan Province, Key Laboratory of Bio-Resources and Eco-Environment, Ministry of Education, 29# Wangjiang Road, Chengdu 610064, China.
| | - Runmin Kang
- Sichuan Animal Science Academy, Sichuan Provincial Key laboratory of Animal Breeding and Genetics, Chengdu 610066, China.
| | - Yi Zhang
- Sichuan Provincial Center for Animal Disease Control and Prevention, Wuhou District, Chengdu 610041, China.
| | - Mengdie Ding
- Sichuan Provincial Center for Animal Disease Control and Prevention, Wuhou District, Chengdu 610041, China.
| | - Bo Xie
- Chengdu Chia Tai Agro-industry & Food Co., Ltd., Animal Healthy Disease Service, Gongping Town, Wenjiang District, Chengdu 610081, China.
| | - Yiming Tian
- School of Life Science, Sichuan University, Animal Disease Prevention and Food Safety Key Laboratory of Sichuan Province, Key Laboratory of Bio-Resources and Eco-Environment, Ministry of Education, 29# Wangjiang Road, Chengdu 610064, China.
| | - Xuan Wu
- School of Life Science, Sichuan University, Animal Disease Prevention and Food Safety Key Laboratory of Sichuan Province, Key Laboratory of Bio-Resources and Eco-Environment, Ministry of Education, 29# Wangjiang Road, Chengdu 610064, China.
| | - Lei Zuo
- School of Life Science, Sichuan University, Animal Disease Prevention and Food Safety Key Laboratory of Sichuan Province, Key Laboratory of Bio-Resources and Eco-Environment, Ministry of Education, 29# Wangjiang Road, Chengdu 610064, China.
| | - Xin Yang
- School of Life Science, Sichuan University, Animal Disease Prevention and Food Safety Key Laboratory of Sichuan Province, Key Laboratory of Bio-Resources and Eco-Environment, Ministry of Education, 29# Wangjiang Road, Chengdu 610064, China.
| | - Hongning Wang
- School of Life Science, Sichuan University, Animal Disease Prevention and Food Safety Key Laboratory of Sichuan Province, Key Laboratory of Bio-Resources and Eco-Environment, Ministry of Education, 29# Wangjiang Road, Chengdu 610064, China.
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Zhou L, Kang R, Xie B, Tian Y, Wu X, Lv X, Yang X, Wang H. Identification of a Novel Recombinant Type 2 Porcine Reproductive and Respiratory Syndrome Virus in China. Viruses 2018; 10:v10040151. [PMID: 29584650 PMCID: PMC5923445 DOI: 10.3390/v10040151] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2018] [Revised: 03/20/2018] [Accepted: 03/22/2018] [Indexed: 01/10/2023] Open
Abstract
Since the emergence of NADC30-like porcine reproductive and respiratory syndrome virus (PRRSV) in China in 2013, PRRSVs have undergone rapid evolution. In this study, a novel variant of PRRSV strain (designated SCcd17) was successfully isolated from piglets with clinical signs in Sichuan Province in China in 2017, and the complete genomic sequence was determined. The genome of this new isolate was 15,015 nucleotides (nt) long, and comparative analysis revealed that SCcd17 exhibited 90.2%, 85.2%, 84.9%, and 84.0% nucleotide similarity to PRRSVs NADC30, JXA1, CH-1a, and VR-2332, respectively. Phylogenetic analysis indicated that the SCcd17 strain was classified into the NADC30-like sub-genotype, in which all the strains contained the unique discontinuous 131-amino acid deletion in nonstructural protein 2 (nsp2) when compared to VR-2332-like viruses. Notably, extensive amino acid substitutions were observed in nsp2 and a unique single amino acid deletion at position 33 of the GP5 is being described for the first time. Strikingly, recombination analysis revealed that SCcd17 was the result of recombination between the NADC30-like, JXA1-like, and VR-2332-like strains at five recombination breakpoints: nsp1α (nt 641), nsp3 (nt 5141), nsp10 (nt 9521), open reading frame 3 (ORF3) (nt 12,581), and ORF4 (nt 13,021). The genomic data of SCcd17 will be helpful for understanding the role of genomic recombination in the evolution of PRRSV.
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Affiliation(s)
- Long Zhou
- School of Life Science, Sichuan University, Animal Disease Prevention and Food Safety Key Laboratory of Sichuan Province, Key Laboratory of Bio-Resources and Eco-Environment, Ministry of Education, 29# Wangjiang Road, Chengdu 610064, China.
| | - Runmin Kang
- Sichuan Animal Science Academy, Sichuan Provincial Key laboratory of Animal Breeding and Genetics, Chengdu 610066, China.
| | - Bo Xie
- Chengdu Chia Tai Agro-Industry & Food Co., Ltd., Animal Healthy Disease Service, Gongping Town, Wenjiang District, Chengdu 610081, China.
| | - Yiming Tian
- School of Life Science, Sichuan University, Animal Disease Prevention and Food Safety Key Laboratory of Sichuan Province, Key Laboratory of Bio-Resources and Eco-Environment, Ministry of Education, 29# Wangjiang Road, Chengdu 610064, China.
| | - Xuan Wu
- School of Life Science, Sichuan University, Animal Disease Prevention and Food Safety Key Laboratory of Sichuan Province, Key Laboratory of Bio-Resources and Eco-Environment, Ministry of Education, 29# Wangjiang Road, Chengdu 610064, China.
| | - Xuebin Lv
- Sichuan Animal Science Academy, Sichuan Provincial Key laboratory of Animal Breeding and Genetics, Chengdu 610066, China.
| | - Xin Yang
- School of Life Science, Sichuan University, Animal Disease Prevention and Food Safety Key Laboratory of Sichuan Province, Key Laboratory of Bio-Resources and Eco-Environment, Ministry of Education, 29# Wangjiang Road, Chengdu 610064, China.
| | - Hongning Wang
- School of Life Science, Sichuan University, Animal Disease Prevention and Food Safety Key Laboratory of Sichuan Province, Key Laboratory of Bio-Resources and Eco-Environment, Ministry of Education, 29# Wangjiang Road, Chengdu 610064, China.
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11
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Molecular characterization and recombination analysis of porcine reproductive and respiratory syndrome virus emerged in southwestern China during 2012-2016. Virus Genes 2017; 54:98-110. [PMID: 29138994 DOI: 10.1007/s11262-017-1519-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Accepted: 11/04/2017] [Indexed: 10/18/2022]
Abstract
Porcine reproductive and respiratory syndrome virus (PRRSV) is an important swine pathogen causing tremendous economic losses to the swine industry. To investigate the prevalence of PRRSV of genotype 2 (North American type, NA-type) in southwestern China, the Nsp2 hypervariable region (Nsp2 HV) and ORF5 of 61 PRRS viruses collected during 2012-2016 were sequenced and analyzed. All the virus detected clustered into the JXA1-like (52/61), VR-2332-like (7/61), and NADC30-like (2/61) sub-genotypes. Five deletions in Nsp2 HV were detected in addition to the typical 30aa discontinuous deletion in HP-PRRSV, and two of these five were not reported previously. Strikingly, two PRRS virus (SCnj16 and SCcd16) isolated in 2016 contained the classic HP-PRRSV molecular marker in the Nsp2-coding region, but belonged to the NADC30-like sub-genotype on the ORF5 gene. Further recombination and phylogenetic analysis on the two complete genomic sequences revealed that they may have originated from recombination events between the NADC30 and Chinese HP-PRRSV strains. The present study suggests that the endemic PRRSVs in the region have continuously evolved and new vaccine strategies are necessary for more efficient control of the virus.
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12
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Liu J, Zhou X, Zhai J, Li B, Wei C, Dai A, Yang X, Luo M. Genetic diversity and evolutionary characteristics of type 2 porcine reproductive and respiratory syndrome virus in southeastern China from 2009 to 2014. Arch Virol 2017; 162:2603-2615. [PMID: 28500445 DOI: 10.1007/s00705-017-3393-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Accepted: 04/26/2017] [Indexed: 11/26/2022]
Abstract
The objective of this study was to assess the genetic diversity of porcine reproductive and respiratory syndrome virus circulating in Fujian province (southeastern China). Based on 53 ORF5 nucleotide sequences collected from nine sites, both highly pathogenic (sublineage 8.7) and lineage 1 strains were circulating in Fujian in 2009-2014 along with lineages 3 and 5.1. Notably, the lineage 1 strains were closely related to the NADC30 strain circulating in North America and were the predominant strains in 2014. In addition, we found that nonstructural protein 2 (NSP2) was the most variable nonstructural protein in Fujian isolates, with a 36-amino-acid (aa) insertion and seven different deletions detected in the 53 sequences examined. Similarly, analysis of GP5 amino acid sequences showed that the isolates were highly variable in primary neutralizing epitopes. Interesting, FJ3.2 and FJ7-2 strains have the mutation N44K, but they exhibited high replication and high titers in MARC-145 and PAM cells. The complete genome sequences determined for 12 type 2 isolates were 82.1-99.3% identical and were 15,016-15,407 nucleotides (nt), in length excluding the poly(A) tail. The strains also shared 88.2-99.4% identity with strain VR2332 (the prototype North American strain), 83.4-99.2% identity with strain JXA1 (the prototype high-pathogenicity Chinese strain), 88.2-97.1% identity with strain CH-1a (the prototype classical Chinese strain), and 82.9-97.1% identity with strain NADC30 (the prototype NADC30-like strain). Strikingly, phylogenetic and molecular evolutionary analyses indicated that strain FJW05 is a spontaneous recombinant between a circulating lineage 1 virus and the vaccine strain JXA1-R, which is derived from the highly pathogenic strain JXA-1. Collectively, the data highlight the epidemiology of porcine reproductive and respiratory syndrome in Fujian and may aid in selecting a suitable vaccine for use on pig farms.
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Affiliation(s)
- Jiankui Liu
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, Guangdong, China
- College of Life Sciences of Longyan University, Longyan, 364012, Fujian, China
- Fujian Provincial Key Laboratory for the Prevention and Control of Animal Infectious Diseases and Biotechnology, Longyan University, Longyan, 364012, Fujian, China
| | - Xia Zhou
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, Guangdong, China
| | - Junqiong Zhai
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, Guangdong, China
| | - Bing Li
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, Guangdong, China
| | - Chunhua Wei
- College of Life Sciences of Longyan University, Longyan, 364012, Fujian, China
- Fujian Provincial Key Laboratory for the Prevention and Control of Animal Infectious Diseases and Biotechnology, Longyan University, Longyan, 364012, Fujian, China
| | - Ailing Dai
- College of Life Sciences of Longyan University, Longyan, 364012, Fujian, China
- Fujian Provincial Key Laboratory for the Prevention and Control of Animal Infectious Diseases and Biotechnology, Longyan University, Longyan, 364012, Fujian, China
| | - Xiaoyan Yang
- College of Life Sciences of Longyan University, Longyan, 364012, Fujian, China.
- Fujian Provincial Key Laboratory for the Prevention and Control of Animal Infectious Diseases and Biotechnology, Longyan University, Longyan, 364012, Fujian, China.
| | - Manlin Luo
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, Guangdong, China
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13
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Recombination in JXA1-R vaccine and NADC30-like strain of porcine reproductive and respiratory syndrome viruses. Vet Microbiol 2017; 204:110-120. [PMID: 28532789 DOI: 10.1016/j.vetmic.2017.04.017] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2016] [Revised: 04/20/2017] [Accepted: 04/20/2017] [Indexed: 11/21/2022]
Abstract
Porcine reproductive and respiratory syndrome (PRRS) is considered one of the most devastating swine diseases worldwide, resulting in immense economic losses. PRRS virus (PRRSV) has undergone rapid evolution since its first recognition in 1990s. In the present study, a PRRSV strain named FJXS15 causing high morbidity and mortality was isolated from piglets and sows from a farm participating in vaccination in China. Phylogenetic and molecular evolutionary analyses revealed that FJXS15 was highly similar to the JXA1-R vaccine strain (a live attenuated virus vaccine strain derived from the highly pathogenic PRRSV JXA1) in the ORF1a (nt 901-)-ORF4 (-nt 419) coding regions, as well as to FJZ03 (lineage 1, NADC30-like) in the 5'-UTR, ORF5a-ORF7 coding regions, and 3'-UTR, suggestive of a natural recombination event. Recombination analyses showed that recombination events occurred in two inter-lineage recombination events between Lineages 1 and 8 based on based on classification system (Shi et al., 2010), and two recombination breakpoints at positions 1-1092 and 13771-15537 of the sequence alignment (with reference to the VR-2332 strain). Animal experiments demonstrated that FJXS15-infected animals had more severe histopathological lung lesions than did JXA1-R-infected and control groups. A 25% mortality rate was found in FJXS15-infected piglets, which was similar to that found with other Chinese HP-PRRSV strains. Thus, the recombinant virus is a highly virulent PRRSV. Moreover, this report provides evidence for inter-subgenotypic recombination between the JXA1-R vaccine virus and a circulating Lineage 1 virus.
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14
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Liu JK, Zhou X, Zhai JQ, Li B, Wei CH, Dai AL, Yang XY, Luo ML. Emergence of a novel highly pathogenic porcine reproductive and respiratory syndrome virus in China. Transbound Emerg Dis 2017; 64:2059-2074. [PMID: 28198110 DOI: 10.1111/tbed.12617] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Indexed: 01/26/2023]
Abstract
From 2014 to 2015, four novel highly pathogenic PRRS virus (HP-PRRSV) strains named 14LY01-FJ, 14LY02-FJ 15LY01-FJ, and 15LY02-FJ were isolated from high morbidity (100%) and mortality (40%-80%) in piglets and sows in Fujian Province. To further our knowledge about these novel virus strains, we characterized their complete genomes and determined their pathogenicity in piglets. Full-length genome sequencing analysis showed that these four isolates were closely related to type 2 (North American type, NA-type) isolates, with 88.1%-96.3% nucleotide similarity, but only 60.6%-60.8% homology to the Lelystad virus (LV) (European type, EU-type). The full length of the four isolates was determined to be 15017 or 15018 nucleotides (nt), excluding the poly(A) tail. Furthermore, the four isolates had three discontinuous deletions (aa 322-432, aa 483, and aa 504-522) within hypervariable region II (HV-II) of Nsp2, as compared to the reference strain VR-2332. This deletion pattern in the four isolates is consistent with strain MN184 and strain NADC30 isolated from America. Phylogenetic and molecular evolutionary analyses indicated that these virulent strains originated from a natural recombination event between the JXA1-like HP-PRRSV (JXA-1 is one of the earliest Chinese HP-PRRSV strains; sublineage 8.7) and the NADC30-like (lineage 1) PRRSV. Animal experiments demonstrated that these four strains caused significant weight loss and severe histopathological lung lesions as compared to the negative control group. High mortality rate (40% or 80%) was found in piglets infected with any one of the four strains, similar to that found with other Chinese HP-PRRSV strains. This study showed that the novel variant PRRSV was HP-PRRSV, and it is therefore critical to monitor PRRSV evolution in China and develop a method for controlling PRRS.
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Affiliation(s)
- J-K Liu
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, Guangdong Province, China.,College of Life Sciences of Longyan University, Longyan, Fujian Province, China.,Fujian Provincial Key Laboratory for the Prevention and Control of Animal Infectious Diseases and Biotechnology, Fujian Province, China
| | - X Zhou
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, Guangdong Province, China
| | - J-Q Zhai
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, Guangdong Province, China
| | - B Li
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, Guangdong Province, China
| | - C-H Wei
- College of Life Sciences of Longyan University, Longyan, Fujian Province, China.,Fujian Provincial Key Laboratory for the Prevention and Control of Animal Infectious Diseases and Biotechnology, Fujian Province, China
| | - A-L Dai
- College of Life Sciences of Longyan University, Longyan, Fujian Province, China.,Fujian Provincial Key Laboratory for the Prevention and Control of Animal Infectious Diseases and Biotechnology, Fujian Province, China
| | - X-Y Yang
- College of Life Sciences of Longyan University, Longyan, Fujian Province, China.,Fujian Provincial Key Laboratory for the Prevention and Control of Animal Infectious Diseases and Biotechnology, Fujian Province, China
| | - M-L Luo
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, Guangdong Province, China
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15
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Complete genomic characterization of two European-genotype porcine reproductive and respiratory syndrome virus isolates in Fujian province of China. Arch Virol 2016; 162:823-833. [PMID: 27858288 DOI: 10.1007/s00705-016-3136-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2016] [Accepted: 10/26/2016] [Indexed: 01/22/2023]
Abstract
Porcine reproductive and respiratory syndrome (PRRS) is considered one of the most devastating swine diseases worldwide, resulting in immense economic losses. PRRS virus (PRRSV) is divided into two major genotypes, European (type 1) and the North American (type 2). Type 1 PRRSV have recently emerged in Fujian province (South China), and this might have a significant impact on the Chinese pig industry. From 2013 to 2014, two type 1 PRRSV strains, named FJEU13 and FJQEU14, were isolated from piglets and sows with respiratory problems and reproductive disorders in Fujian province. The full genome length of the two isolates was 14,869-15,062 nucleotides (nt), excluding the poly(A) tail. These isolates shared 86.0-89.9% sequence identity with the prototypic strains Lelystad virus (LV) and 82.8-92% with Chinese type 1 PRRSV strains, but only 59.9-60.1% with the North American reference strain VR-2332. However, they were 82.9% identical to each other. Nonstructural protein 2 (Nsp2) and ORF3-ORF5 were the most variable regions when compared to other type 1 PRRSV strains. Nsp2 and ORF3 contained multiple discontinuous deletions and a 204-bp deletion in NSP2 in isolate FJQEU14, which has never been described in other Chinese type 1 PRRSV strains. All of these results might be useful for understanding the epidemic status of type 1 PRRSV in China.
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16
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Liu Y, Wang FX, Wen YJ, Li ZG, Liu X, Sun N, Yang Y, Zhang SQ, Zhu HW, Cheng SP, Wu H. Effect of Nonstructural Protein 2 Hypervariable Regions in the Replication of Porcine Reproductive and Respiratory Syndrome Virus in Marc-145 Cells. Intervirology 2015; 58:288-96. [PMID: 26694645 DOI: 10.1159/000440977] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Accepted: 09/08/2015] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Highly pathogenic (HP) porcine reproductive and respiratory syndrome virus (PRRSV) causes prolonged high fever, red discoloration of the body, blue ears and a high mortality. Previously, we found that the PRRSV vaccine strain TJM contained a deletion of 120 amino acids (aa 628-747) in nonstructural protein 2 (Nsp2). We aimed to explore the replication features of PRRSV after adding the transiently expressed product of these 120 aa in vitro. METHODS We constructed seven eukaryotic expression plasmids containing different parts of the 120-aa sequence, transfected them into Marc-145 cells and then inoculated the cells with 103 TCID50 TJM per well. We detected virus replication at mRNA and protein level by real-time RT-PCR and Western blotting, respectively, and determined the virus titer. RESULTS The transiently expressed 120 aa and one of its truncated polypeptides inhibited PRRSV TJM propagation on Marc-145 cells. The complete 120-aa sequence induced a remarkable decrease in PRRSV replication, causing a reduction in structural protein levels between 36 and 48 h after infection. Additionally, aa 628-727 partly reduced the replication of PRRSV on Marc-145 cells. CONCLUSIONS The 120 aa from Nsp2, especially aa 628-727, play a negative role in PRRSV TJM proliferation.
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Affiliation(s)
- Ying Liu
- State Key Laboratory for Molecular Biology of Special Economic Animals, Institute of Special Economic Animal and Plant Sciences, Chinese Academy of Agricultural Sciences, Changchun, China
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17
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Do DT, Park C, Choi K, Jeong J, Nguyen TT, Le DTH, Vo KM, Chae C. Nucleotide sequence analysis of Vietnamese highly pathogenic porcine reproductive and respiratory syndrome virus from 2013 to 2014 based on the NSP2 and ORF5 coding regions. Arch Virol 2015; 161:669-75. [PMID: 26615550 DOI: 10.1007/s00705-015-2699-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Accepted: 11/19/2015] [Indexed: 11/26/2022]
Abstract
A total of 34 highly pathogenic porcine reproductive and respiratory syndrome virus (HP-PRRSV) strains isolated from Vietnam during 2013-2014 were sequenced and analyzed. A partial sequence of ORF1a corresponding to the nonstructural protein 2 (Nsp2) coding region and the full sequence of open reading frame 5 (ORF5) gene was used for the analysis. The HP-PRRSV strains were isolated from pig herds that had never been vaccinated for PRRSV. Nucleotide sequence identities in the portions of ORF1a corresponding to the nonstructural protein 2 (Nsp2) coding region and ORF5 ranged from 96.4 to 100 % and 83.2 to 100 %, respectively. All of the 34 Vietnamese HP-PRRSV strains showed two discontinuous 30-amino-acid deletions in the Nsp2 coding region as a genetic marker of prototypic Chinese HP-PRRSV. The amino acid arginine (R) was present at positions 13 and 151 in ORF5 in 29 out of 34 Vietnamese HP-PRRSV isolates, as well as in the prototypic Chinese HP-PRRSV. Sequence analysis of the ORF5 genes of all Vietnamese HP-PRRSVs revealed six subgroups: Viet 1 to 4, JAX1-like, and VR-2332-like. Nucleotide and amino acid sequence analysis of 34 Vietnamese HP-PRRSV isolates from 2013-2014 indicated that Vietnamese HP-PRRSV has undergone rapid evolutionary changes in recent years when compared with Vietnamese HP-PRRSV isolated before 2012.
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Affiliation(s)
- Duy Tien Do
- Department of Veterinary Pathology, College of Veterinary Medicine, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 151-742, Republic of Korea
- Faculty of Animal Husbandry and Veterinary Medicine, Nonglam University, Thu Duc District, Ho Chi Minh, Vietnam
| | - Changhoon Park
- Department of Veterinary Pathology, College of Veterinary Medicine, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 151-742, Republic of Korea
| | - Kyuhyung Choi
- Department of Veterinary Pathology, College of Veterinary Medicine, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 151-742, Republic of Korea
| | - Jiwoon Jeong
- Department of Veterinary Pathology, College of Veterinary Medicine, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 151-742, Republic of Korea
| | - Toan Tat Nguyen
- Faculty of Animal Husbandry and Veterinary Medicine, Nonglam University, Thu Duc District, Ho Chi Minh, Vietnam
| | - Dung Thi Hanh Le
- Faculty of Animal Husbandry and Veterinary Medicine, Nonglam University, Thu Duc District, Ho Chi Minh, Vietnam
| | - Khoa Minh Vo
- Faculty of Animal Husbandry and Veterinary Medicine, Nonglam University, Thu Duc District, Ho Chi Minh, Vietnam
| | - Chanhee Chae
- Department of Veterinary Pathology, College of Veterinary Medicine, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 151-742, Republic of Korea.
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18
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Chen Y, He S, Sun L, Luo Y, Sun Y, Xie J, Zhou P, Su S, Zhang G. Genetic variation, pathogenicity, and immunogenicity of highly pathogenic porcine reproductive and respiratory syndrome virus strain XH-GD at different passage levels. Arch Virol 2015; 161:77-86. [PMID: 26483282 DOI: 10.1007/s00705-015-2597-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2015] [Accepted: 09/02/2015] [Indexed: 02/01/2023]
Abstract
Porcine reproductive and respiratory syndrome (PRRS) is one of the most economically important infectious diseases of swine worldwide. Immunization with an attenuated vaccine is considered an effective method for reducing the economic losses resulting from porcine reproductive and respiratory syndrome virus (PRRSV) infection. Several studies have shown that PRRSV can be attenuated by passage in Marc-145 cells, but it is still not clear whether this attenuation influences the immunogenicity of PRRSV and what the mechanism of attenuation is. In order to study the mechanism of attenuation and immunogenicity of highly pathogenic (HP) PRRSV, the HP-PRRSV strain XH-GD was serially 122 times passaged in Marc-145 cells. Genomic sequence comparisons were made at selected passages. To explore the differences in pathogenicity and immunogenicity at different passages, three passages (P5, P62 and P122) were selected for an animal challenge experiment, which showed that passage in Marc-145 cells resulted in attenuation of the virus. After 122 passages, 35 amino acid changes were observed in the structural proteins and non-structural proteins. The animal challenge experiment showed that pathogenicity decreased with increasing passage number. The N antibody level and specific neutralizing (SN) antibody titers also decreased with increasing passage number in the late stage of the animal experiment. This study indicated that the virulence of XH-GD was decreased by passage in Marc-145 cells and that overattenuation might influence the immunogenicity of virus. These results might contribute to our understanding of the mechanism of attenuation.
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Affiliation(s)
- Yao Chen
- MOA Key Laboratory of Animal Vaccine Development, Ministry of China, College of Veterinary Medicine, South China Agricultural University, 483 Wushan Road, Tianhe District, Guangzhou, 510642, China
| | - Shuyi He
- MOA Key Laboratory of Animal Vaccine Development, Ministry of China, College of Veterinary Medicine, South China Agricultural University, 483 Wushan Road, Tianhe District, Guangzhou, 510642, China
| | - Long Sun
- MOA Key Laboratory of Animal Vaccine Development, Ministry of China, College of Veterinary Medicine, South China Agricultural University, 483 Wushan Road, Tianhe District, Guangzhou, 510642, China
| | - Yongfeng Luo
- MOA Key Laboratory of Animal Vaccine Development, Ministry of China, College of Veterinary Medicine, South China Agricultural University, 483 Wushan Road, Tianhe District, Guangzhou, 510642, China
| | - Yankuo Sun
- MOA Key Laboratory of Animal Vaccine Development, Ministry of China, College of Veterinary Medicine, South China Agricultural University, 483 Wushan Road, Tianhe District, Guangzhou, 510642, China
| | - Jiexiong Xie
- MOA Key Laboratory of Animal Vaccine Development, Ministry of China, College of Veterinary Medicine, South China Agricultural University, 483 Wushan Road, Tianhe District, Guangzhou, 510642, China
| | - Pei Zhou
- Guangdong Provincial Key Laboratory of Prevention and Control for Severe Clinical Animal Diseases, College of Veterinary Medicine, South China Agricultural University, 483 Wushan Road, Tianhe District, Guangzhou, 510642, China
| | - Shuo Su
- Guangdong Provincial Key Laboratory of Prevention and Control for Severe Clinical Animal Diseases, College of Veterinary Medicine, South China Agricultural University, 483 Wushan Road, Tianhe District, Guangzhou, 510642, China
| | - Guihong Zhang
- MOA Key Laboratory of Animal Vaccine Development, Ministry of China, College of Veterinary Medicine, South China Agricultural University, 483 Wushan Road, Tianhe District, Guangzhou, 510642, China.
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19
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Deng MC, Chang CY, Huang TS, Tsai HJ, Chang C, Wang FI, Huang YL. Molecular epidemiology of porcine reproductive and respiratory syndrome viruses isolated from 1991 to 2013 in Taiwan. Arch Virol 2015; 160:2709-18. [PMID: 26246243 DOI: 10.1007/s00705-015-2554-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2015] [Accepted: 07/17/2015] [Indexed: 10/23/2022]
Abstract
Porcine reproductive and respiratory syndrome virus (PRRSV) was first identified in Taiwan in 1991, but the genetic diversity and evolution of PRRSV has not been thoroughly investigated over the past 20 years. The aim of this study was to bridge the gap in understanding of its molecular epidemiology. A total of 31 PRRSV strains were collected and sequenced. The sequences were aligned using the MUSCLE program, and phylogenetic analysis were performed by the maximum-likelihood method and the neighbor-joining method using MEGA 5.2 software. In the early 1990s, two prototype strains, WSV and MD001 of the North American genotype, were first identified. Over the years, both viruses evolved separately. The population dynamics of PRRSV revealed that the strains of the MD001 group were predominant in Taiwan. Evolution was manifested in changes in the nsp2 and ORF5 genes. In addition, a suspected newly invading exotic strain was recovered in 2013, suggesting that international spread is still taking place and that it is affecting the population dynamics. Overall, the results provide an important basis for vaccine development for the control and prevention of PRRS.
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Affiliation(s)
- Ming-Chung Deng
- Animal Health Research Institute, Council of Agriculture, 376 Chung-Cheng Road, Tansui, New Taipei, 25158, Taiwan
| | - Chia-Yi Chang
- Animal Health Research Institute, Council of Agriculture, 376 Chung-Cheng Road, Tansui, New Taipei, 25158, Taiwan.
| | - Tien-Shine Huang
- Animal Health Research Institute, Council of Agriculture, 376 Chung-Cheng Road, Tansui, New Taipei, 25158, Taiwan
| | - Hsiang-Jung Tsai
- Animal Health Research Institute, Council of Agriculture, 376 Chung-Cheng Road, Tansui, New Taipei, 25158, Taiwan.,School of Veterinary Medicine, National Taiwan University, No. 1, Section 4, Roosevelt Road, Taipei, 10617, Taiwan
| | - Chieh Chang
- Animal Health Research Institute, Council of Agriculture, 376 Chung-Cheng Road, Tansui, New Taipei, 25158, Taiwan
| | - Fun-In Wang
- School of Veterinary Medicine, National Taiwan University, No. 1, Section 4, Roosevelt Road, Taipei, 10617, Taiwan
| | - Yu-Liang Huang
- Animal Health Research Institute, Council of Agriculture, 376 Chung-Cheng Road, Tansui, New Taipei, 25158, Taiwan.
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20
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Zuo Y, Yuan W, Sun J. Complete Genomic Characterization of Porcine Reproductive and Respiratory Syndrome Virus Strain HB-XL. Genes (Basel) 2015. [PMID: 26213972 PMCID: PMC4584324 DOI: 10.3390/genes6030672] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Porcine reproductive and respiratory syndrome virus (PRRSV) is the causal agent of a serious disease of swine. Here, we report the genome sequence of PRRSV strain HB-XL isolated from a pig farm with a clinical outbreak of porcine reproductive and respiratory syndrome. The genome is 15,323 bp long and has nine open reading frames (GenBank: KP162169). Comparative and phylogenetic analysis showed that HB-XL belongs to the highly pathogenic PRRSV (HP-PRRSV) subfamily in the family PRRSV. The viral nonstructural protein 2 (Nsp2) of the HB-XL strain contained 30 discontinuous amino acid (AA) deletions relative to that of the Nsp2 of the VR2332 strain. The AA substitutions R13 and R151 suggested high virulence of the HB-XL strain. The unique mutations in glycoprotein 5 (GP5) and Nsp2 revealed that HB-XL might be a novel variant PRRSV strain recombined with vaccine strains. However, the low morbidity and mortality in the pig herd from which HB-XL was isolated indicate that the virulence of the virus was weak, so it has potential as a future vaccine strain.
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Affiliation(s)
- Yi Zuo
- College of Animal Medicine, Agriculture University of Hebei, Baoding 071001, China.
- Hebei Engineering and Technology Research Center of Veterinary Biotechnology, Baoding 071001, China.
| | - Wanzhe Yuan
- College of Animal Medicine, Agriculture University of Hebei, Baoding 071001, China.
- Hebei Engineering and Technology Research Center of Veterinary Biotechnology, Baoding 071001, China.
| | - Jiguo Sun
- College of Animal Medicine, Agriculture University of Hebei, Baoding 071001, China.
- Hebei Engineering and Technology Research Center of Veterinary Biotechnology, Baoding 071001, China.
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21
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Jiang YF, Xia TQ, Zhou YJ, Yu LX, Yang S, Huang QF, Li LW, Gao F, Qu ZH, Tong W, Tong GZ. Characterization of three porcine reproductive and respiratory syndrome virus isolates from a single swine farm bearing strong homology to a vaccine strain. Vet Microbiol 2015; 179:242-9. [PMID: 26162970 DOI: 10.1016/j.vetmic.2015.06.015] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Revised: 06/25/2015] [Accepted: 06/26/2015] [Indexed: 11/16/2022]
Abstract
Three porcine reproductive and respiratory syndrome viruses (PRRSV), NT1, NT2, and NT3, were isolated from three dying piglets from a single pig farm in Jiangsu Province, China. Whole genome sequencing revealed that the three isolates share the highest homology with JXA1-P80, an attenuated vaccine strain developed by serial passage of highly pathogenic PRRSV JXA1 in MARC-145 cells. More than ten amino acids residues in ORF1a, ORF1b, GP4, and GP5 that were thought to be unique to JXA1 attenuated on MARC-145 cells were each found in the corresponding locations of NT1, NT2, and NT3. In virulence assays, piglets infected with NT1, NT2, or NT3 exhibited clinical signs of disease, including high fever, anorexia, and respiratory distress, leading to the death of the majority of the piglets within two weeks. Collectively, these data indicate that NT1, NT2, and NT3 are highly pathogenic PRRSVs and they are likely to be revertants of the vaccine strain JXA1-P80.
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Affiliation(s)
- Yi-feng Jiang
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou 225009, China
| | - Tian-qi Xia
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Yan-jun Zhou
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou 225009, China
| | - Ling-xue Yu
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Shen Yang
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Qin-feng Huang
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Li-wei Li
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Fei Gao
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Ze-hui Qu
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Wu Tong
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Guang-zhi Tong
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou 225009, China
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22
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Wang J, Wen H, Wang S, Sun W, Shen N, Liu Z, Liu Y, Liu Y, Jiang C, Sun G, Goutard F, Cai X. Preliminary Study on Prevalence, Risk Factor and Genetic Homogeneity of Porcine Reproductive and Respiratory Syndrome Virus in Registered Pig Farms in Heilongjiang, China. Transbound Emerg Dis 2015; 63:e369-80. [DOI: 10.1111/tbed.12312] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2014] [Indexed: 11/27/2022]
Affiliation(s)
- J. Wang
- Animal Infectious Disease Diagnostic Center and National Key Laboratory of Veterinary Biotechnology; Harbin Veterinary Research Institute; Chinese Academy of Agricultural Sciences; Harbin China
| | - H. Wen
- Animal Infectious Disease Diagnostic Center and National Key Laboratory of Veterinary Biotechnology; Harbin Veterinary Research Institute; Chinese Academy of Agricultural Sciences; Harbin China
| | - S. Wang
- Animal Infectious Disease Diagnostic Center and National Key Laboratory of Veterinary Biotechnology; Harbin Veterinary Research Institute; Chinese Academy of Agricultural Sciences; Harbin China
| | - W. Sun
- Animal Infectious Disease Diagnostic Center and National Key Laboratory of Veterinary Biotechnology; Harbin Veterinary Research Institute; Chinese Academy of Agricultural Sciences; Harbin China
| | - N. Shen
- Animal Infectious Disease Diagnostic Center and National Key Laboratory of Veterinary Biotechnology; Harbin Veterinary Research Institute; Chinese Academy of Agricultural Sciences; Harbin China
| | - Z. Liu
- Animal Infectious Disease Diagnostic Center and National Key Laboratory of Veterinary Biotechnology; Harbin Veterinary Research Institute; Chinese Academy of Agricultural Sciences; Harbin China
| | - Y. Liu
- Animal Infectious Disease Diagnostic Center and National Key Laboratory of Veterinary Biotechnology; Harbin Veterinary Research Institute; Chinese Academy of Agricultural Sciences; Harbin China
| | - Y. Liu
- Animal Infectious Disease Diagnostic Center and National Key Laboratory of Veterinary Biotechnology; Harbin Veterinary Research Institute; Chinese Academy of Agricultural Sciences; Harbin China
| | - C. Jiang
- Animal Infectious Disease Diagnostic Center and National Key Laboratory of Veterinary Biotechnology; Harbin Veterinary Research Institute; Chinese Academy of Agricultural Sciences; Harbin China
| | - G. Sun
- Heilongjiang Institute of Animal Health Inspection; Harbin China
| | - F. Goutard
- International Centre of Research in Agronomy for Development; Montpellier France
| | - X. Cai
- Animal Infectious Disease Diagnostic Center and National Key Laboratory of Veterinary Biotechnology; Harbin Veterinary Research Institute; Chinese Academy of Agricultural Sciences; Harbin China
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23
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Chaikhumwang P, Tantituvanont A, Tripipat T, Tipsombatboon P, Piriyapongsa J, Nilubol D. Dynamics and evolution of highly pathogenic porcine reproductive and respiratory syndrome virus following its introduction into a herd concurrently infected with both types 1 and 2. INFECTION GENETICS AND EVOLUTION 2014; 30:164-174. [PMID: 25557456 DOI: 10.1016/j.meegid.2014.12.025] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Revised: 12/19/2014] [Accepted: 12/21/2014] [Indexed: 11/28/2022]
Abstract
Since its first emergence in Thailand in late 2010, highly pathogenic porcine reproductive and respiratory syndrome virus (HP-PRRSV) has caused sporadic outbreaks on Thai swine farms. The objective of this study was to investigate the dynamics and evolution of PRRSV in a herd experiencing an HP-PRRSV outbreak. Following its introduction, HP-PRRSV caused severe outbreaks and subsequently established persistent infection in the herd, resulting in the emergence of a novel cluster of type 2 (North American, NA) isolates. HP-PRRSV co-existed with type 1 (European, EU) isolates without influencing their development. In contrast, HP-PRRSV influenced the evolution of the type 2 (NA) isolates by increasing diversity through the addition of a novel cluster and influencing the evolution of other viral clusters previously existing in the herd. Recombination between the endemic and emerging isolates was observed. The recombinants, however, disappeared and were not able to survive in the herd. The results of this study suggest that the introduction of HP-PRRSV to a herd results in an increased diversity of genetically related isolates and persistent HP-PRRSV infection.
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Affiliation(s)
- Puwich Chaikhumwang
- Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmaceutical Sciences, Chulalongkorn University, Bangkok 10330, Thailand
| | - Angkana Tantituvanont
- Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmaceutical Sciences, Chulalongkorn University, Bangkok 10330, Thailand
| | - Thitima Tripipat
- Department of Veterinary Microbiology, Faculty of Veterinary Science, Bangkok 10330, Thailand
| | - Pavita Tipsombatboon
- Genome Institute, National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, Pathumthani 12120, Thailand
| | - Jittima Piriyapongsa
- Genome Institute, National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, Pathumthani 12120, Thailand
| | - Dachrit Nilubol
- Department of Veterinary Microbiology, Faculty of Veterinary Science, Bangkok 10330, Thailand.
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24
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Leng CL, Tian ZJ, Zhang WC, Zhang HL, Zhai HY, An TQ, Peng JM, Ye C, Sun L, Wang Q, Sun Y, Li L, Zhao HY, Chang D, Cai XH, Zhang GH, Tong GZ. Characterization of two newly emerged isolates of porcine reproductive and respiratory syndrome virus from Northeast China in 2013. Vet Microbiol 2014; 171:41-52. [DOI: 10.1016/j.vetmic.2014.03.005] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2013] [Revised: 02/17/2014] [Accepted: 03/03/2014] [Indexed: 11/28/2022]
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