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Genetic variability and distribution of Classical swine fever virus

Published online by Cambridge University Press:  08 June 2015

Martin Beer*
Affiliation:
Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Suedufer 10, 17493 Greifswald–Insel Riems, Germany
Katja V. Goller
Affiliation:
Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Suedufer 10, 17493 Greifswald–Insel Riems, Germany
Christoph Staubach
Affiliation:
Institute of Epidemiology, Friedrich-Loeffler-Institut, Suedufer 10, 17493 Greifswald–Insel Riems, Germany
Sandra Blome
Affiliation:
Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Suedufer 10, 17493 Greifswald–Insel Riems, Germany
*
*Corresponding author. E-mail: [email protected]

Abstract

Classical swine fever is a highly contagious disease that affects domestic and wild pigs worldwide. The causative agent of the disease is Classical swine fever virus (CSFV), which belongs to the genus Pestivirus within the family Flaviviridae. On the genome level, CSFV can be divided into three genotypes with three to four sub-genotypes. Those genotypes can be assigned to distinct geographical regions. Knowledge about CSFV diversity and distribution is important for the understanding of disease dynamics and evolution, and can thus help to design optimized control strategies. For this reason, the geographical pattern of CSFV diversity and distribution are outlined in the presented review. Moreover, current knowledge with regard to genetic virulence markers or determinants and the role of the quasispecies composition is discussed.

Type
Review Article
Copyright
Copyright © Cambridge University Press 2015 

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References

Barman, NN, Bora, DP, Khatoon, E, Mandal, S, Rakshit, A, Rajbongshi, G, Depner, K, Chakraborty, A and Kumar, S (2014). Classical Swine Fever in Wild Hog: Report of its Prevalence in Northeast India. Transboundary and Emerging Diseases doi: 10.1111/tbed.12298.Google ScholarPubMed
Bartak, P and Greiser-Wilke, I (2000). Genetic typing of classical swine fever virus isolates from the territory of the Czech Republic. Veterinary Microbiology 77: 5970.CrossRefGoogle ScholarPubMed
Biagetti, M, Greiser-Wilke, I and Rutili, D (2001). Molecular epidemiology of classical swine fever in Italy. Veterinary Microbiology 83: 205215.CrossRefGoogle ScholarPubMed
Bintintan, I and Meyers, G (2010). A new type of signal peptidase cleavage site identified in an RNA virus polyprotein. Journal of Biological Chemistry 285: 85728584.CrossRefGoogle Scholar
Björklund, H, Lowings, P, Stadejek, T, Vilcek, S, Greiser-Wilke, I, Paton, D and Belak, S (1999). Phylogenetic comparison and molecular epidemiology of classical swine fever virus. Virus Genes 19: 189195.CrossRefGoogle ScholarPubMed
Blacksell, SD, Khounsy, S, Boyle, DB, Greiser-Wilke, I, Gleeson, LJ, Westbury, HA and Mackenzie, JS (2004). Phylogenetic analysis of the E2 gene of classical swine fever viruses from Lao PDR. Virus Research 104: 8792.CrossRefGoogle ScholarPubMed
Blacksell, SD, Khounsy, S, Boyle, DB, Gleeson, LJ, Westbury, HA and Mackenzie, JS (2005). Genetic typing of classical swine fever viruses from Lao PDR by analysis of the 5′ non-coding region. Virus Genes 31: 349355.CrossRefGoogle ScholarPubMed
Blome, S, Gabriel, C, Schmeiser, S, Meyer, D, Meindl-Bohmer, A, Koenen, F and Beer, M (2014). Efficacy of marker vaccine candidate CP7_E2alf against challenge with classical swine fever virus isolates of different genotypes. Veterinary Microbiology 169: 817.CrossRefGoogle ScholarPubMed
Blome, S, Grotha, I, Moennig, V and Greiser-Wilke, I (2010). Classical swine fever virus in South-Eastern Europe–retrospective analysis of the disease situation and molecular epidemiology. Veterinary Microbiology 146: 276284.CrossRefGoogle ScholarPubMed
Cha, SH, Choi, EJ, Park, JH, Yoon, SR, Kwon, JH, Yoon, KJ and Song, JY (2007). Phylogenetic characterization of classical swine fever viruses isolated in Korea between 1988 and 2003. Virus Research 126: 256261.CrossRefGoogle ScholarPubMed
Chen, N, Hu, H, Zhang, Z, Shuai, J, Jiang, L and Fang, W (2008). Genetic diversity of the envelope glycoprotein E2 of classical swine fever virus: recent isolates branched away from historical and vaccine strains. Veterinary Microbiology 127: 286299.CrossRefGoogle ScholarPubMed
Collett, MS (1992). Molecular genetics of pestiviruses. Comparative Immunology, Microbiology and Infectious Disease 15: 145154.CrossRefGoogle ScholarPubMed
David, D, Edri, N, Yakobson, BA, Bombarov, V, King, R, Davidson, I, Pozzi, P, Hadani, Y, Bellaiche, M, Schmeiser, S and Perl, S (2011). Emergence of classical swine fever virus in Israel in 2009. Veterinary Journal 190: e146e149.CrossRefGoogle ScholarPubMed
de Arce, HD, Ganges, L, Barrera, M, Naranjo, D, Sobrino, F, Frias, MT and Nunez, JI (2005). Origin and evolution of viruses causing classical swine fever in Cuba. Virus Research 112: 123131.CrossRefGoogle ScholarPubMed
Deng, MC, Huang, CC, Huang, TS, Chang, CY, Lin, YJ, Chien, MS and Jong, MH (2005). Phylogenetic analysis of classical swine fever virus isolated from Taiwan. Veterinary Microbiology 106: 187193.CrossRefGoogle ScholarPubMed
Depner, KR, Strebelow, G, Staubach, C, Kramer, M, Teuffert, J, Botcher, L, Hoffmann, B, Beer, M, Greiser-Wilke, I and Mettenleiter, T (2006). Case report: the significance of genotyping for the epidemiological tracing of classical swine fever (CSF). Dtsch Tierarztl Wochenschr 113: 159162.Google ScholarPubMed
Desai, GS, Sharma, A, Kataria, RS, Barman, NN and Tiwari, AK (2010). 5′-UTR-based phylogenetic analysis of Classical swine fever virus isolates from India. Acta Virology 54: 7982.CrossRefGoogle ScholarPubMed
Dreier, S, Zimmermann, B, Moennig, V and Greiser-Wilke, I (2007). A sequence database allowing automated genotyping of Classical swine fever virus isolates. Journal of Virological Methods 140: 9599.CrossRefGoogle ScholarPubMed
Eigen, M (1971). Selforganization of matter and the evolution of biological macromolecules. Die Naturwissenschaften 58: 465523.CrossRefGoogle ScholarPubMed
Elbers, K, Tautz, N, Becher, P, Stoll, D, Rumenapf, T and Thiel, HJ (1996). Processing in the pestivirus E2-NS2 region: identification of proteins p7 and E2p7. Journal of Virology 70: 41314135.CrossRefGoogle ScholarPubMed
Fahnoe, U, Pedersen, AG, Risager, PC, Nielsen, J, Belsham, GJ, Hoper, D, Beer, M and Rasmussen, TB (2014). Rescue of the highly virulent classical swine fever virus strain “Koslov” from cloned cDNA and first insights into genome variations relevant for virulence. Virology 468–470: 379387.CrossRefGoogle ScholarPubMed
Fernandez-Sainz, I, Holinka, LG, Gavrilov, BK, Prarat, MV, Gladue, D, Lu, Z, Jia, W, Risatti, GR and Borca, MV (2009). Alteration of the N-linked glycosylation condition in E1 glycoprotein of Classical Swine Fever Virus strain Brescia alters virulence in swine. Virology 386: 210216.CrossRefGoogle ScholarPubMed
Fritzemeier, J, Teuffert, J, Greiser-Wilke, I, Staubach, C, Schluter, H and Moennig, V (2000). Epidemiology of classical swine fever in Germany in the 1990s. Veterinary Microbiology 77: 2941.CrossRefGoogle ScholarPubMed
Gladue, DP, Holinka, LG, Fernandez-Sainz, IJ, Prarat, MV, O'Donell, V, Vepkhvadze, N, Lu, Z, Rogers, K, Risatti, GR and Borca, MV (2010). Effects of the interactions of classical swine fever virus Core protein with proteins of the SUMOylation pathway on virulence in swine. Virology 407: 129136.CrossRefGoogle ScholarPubMed
Gladue, DP, Holinka, LG, Fernandez-Sainz, IJ, Prarat, MV, O'Donnell, V, Vepkhvadze, NG, Lu, Z, Risatti, GR and Borca, MV (2011). Interaction between Core protein of classical swine fever virus with cellular IQGAP1 protein appears essential for virulence in swine. Virology 412: 6874.Google Scholar
Graham, SP, Everett, HE, Haines, FJ, Johns, HL, Sosan, OA, Salguero, FJ, Clifford, DJ, Steinbach, F, Drew, TW and Crooke, HR (2012). Challenge of pigs with classical swine fever viruses after C-strain vaccination reveals remarkably rapid protection and insights into early immunity. PLoS ONE 7: e29310.CrossRefGoogle ScholarPubMed
Greiser-Wilke, I, Depner, K, Fritzemeier, J, Haas, L and Moennig, V (1998). Application of a computer program for genetic typing of classical swine fever virus isolates from Germany. Journal of Virological Methods 75: 141150.CrossRefGoogle ScholarPubMed
Greiser-Wilke, I, Fritzemeier, J, Koenen, F, Vanderhallen, H, Rutili, D, De Mia, GM, Romero, L, Rosell, R, Sanchez-Vizcaino, JM and San Gabriel, A (2000). Molecular epidemiology of a large classical swine fever epidemic in the European Union in 1997–1998. Veterinary Microbiology 77: 1727.CrossRefGoogle ScholarPubMed
Holland, JJ, De La Torre, JC and Steinhauer, DA (1992). RNA virus populations as quasispecies. Current Topics in Microbiology and Immunology 176: 120.Google ScholarPubMed
Ishikawa, K, Nagai, H, Katayama, K, Tsutsui, M, Tanabayashi, K, Takeuchi, K, Hishiyama, M, Saitoh, A, Takagi, M, Gotoh, K, Muramatsu, M, Yamada, A (1995). Comparison of the entire nucleotide and deduced amino acid sequences of the attenuated hog cholera vaccine strain GPE- and the wild-type parental strain ALD. Archives of Virology 140: 13851391.CrossRefGoogle ScholarPubMed
Jemersic, L, Greiser-Wilke, I, Barlic-Maganja, D, Lojkic, M, Madic, J, Terzic, S and Grom, J (2003). Genetic typing of recent classical swine fever virus isolates from Croatia. Veterinary Microbiology 96: 2533.CrossRefGoogle ScholarPubMed
Jiang, DL, Gong, WJ, Li, RC, Liu, GH, Hu, YF, Ge, M, Wang, SQ, Yu, XL and Tu, C (2013). Phylogenetic analysis using E2 gene of classical swine fever virus reveals a new subgenotype in China. Infection, Genetics and Evolution 17: 231238.CrossRefGoogle ScholarPubMed
Lattwein, E, Klemens, O, Schwindt, S, Becher, P and Tautz, N (2012). Pestivirus virion morphogenesis in the absence of uncleaved nonstructural protein 2–3. Journal of Virology 86: 427437.CrossRefGoogle ScholarPubMed
Lauring, AS and Andino, R (2010). Quasispecies theory and the behavior of RNA viruses. PLoS Pathogens 6: e1001005.CrossRefGoogle ScholarPubMed
Leifer, I, Hoffmann, B, Hoper, D, Bruun Rasmussen, T, Blome, S, Strebelow, G, Horeth-Bontgen, D, Staubach, C and Beer, M (2010). Molecular epidemiology of current classical swine fever virus isolates of wild boar in Germany. Journal of General Virology 91: 26872697.CrossRefGoogle ScholarPubMed
Leifer, I, Ruggli, N and Blome, S (2013). Approaches to define the viral genetic basis of classical swine fever virus virulence. Virology 438: 5155.CrossRefGoogle ScholarPubMed
Lin, YJ, Chien, MS, Deng, MC and Huang, CC (2007). Complete sequence of a subgroup 3.4 strain of classical swine fever virus from Taiwan. Virus Genes 35: 737744.CrossRefGoogle ScholarPubMed
Lindenbach, BD, Murray, CL, Thiel, HJ and Rice, CM (2013). Flaviviridae. In: Knipe, DM and Howley, PM (ed) Fields Virology. Philadelphia, PA: Lippincott Williams and Wilkins, pp. 712747.Google Scholar
Lowings, P, Ibata, G, Needham, J and Paton, D (1996). Classical swine fever virus diversity and evolution. Journal of General Virology 77 (Pt 6): 13111321.CrossRefGoogle ScholarPubMed
Luo, TR, Liao, SH, Wu, XS, Feng, L, Yuan, ZX, Li, H, Liang, JJ, Meng, XM and Zhang, HY (2011). Phylogenetic analysis of the E2 gene of classical swine fever virus from the Guangxi Province of southern China. Virus Genes 42: 347354.CrossRefGoogle ScholarPubMed
Luo, Y, Li, S, Sun, Y and Qiu, HJ (2014). Classical swine fever in China: a mini review. Veterinary Microbiology 172: 16.CrossRefGoogle Scholar
Mayer, D, Hofmann, MA and Tratschin, JD (2004). Attenuation of classical swine fever virus by deletion of the viral N(pro) gene. Vaccine 22: 317328.Google Scholar
Meyers, G, Thiel, HJ and Rumenapf, T (1996). Classical swine fever virus: recovery of infectious viruses from cDNA constructs and generation of recombinant cytopathogenic defective interfering particles. Journal of Virology 70: 15881595.CrossRefGoogle ScholarPubMed
Meyers, G, Saalmuller, A and Buttner, M (1999). Mutations abrogating the RNase activity in glycoprotein E(rns) of the pestivirus classical swine fever virus lead to virus attenuation. Journal of Virology 73: 1022410235.CrossRefGoogle ScholarPubMed
Nandi, S, Muthuchelvan, D, Ahuja, A, Bisht, S, Chander, V, Pandey, AB and Singh, RK (2011). Prevalence of classical swine fever virus in India: a 6-year study (2004–2010). Transboundary and Emergerging Disease 58: 461463.Google Scholar
Pan, CH, Jong, MH, Huang, TS, Liu, HF, Lin, SY and Lai, SS (2005). Phylogenetic analysis of classical swine fever virus in Taiwan. Archives of Virology 150: 11011119.CrossRefGoogle ScholarPubMed
Patil, SS, Hemadri, D, Shankar, BP, Raghavendra, AG, Veeresh, H, Sindhoora, B, Chandan, S, Sreekala, K, Gajendragad, MR and Prabhudas, K (2010). Genetic typing of recent classical swine fever isolates from India. Veterinary Microbiology 141: 367373.CrossRefGoogle ScholarPubMed
Patil, SS, Hemadri, D, Veeresh, H, Sreekala, K, Gajendragad, MR and Prabhudas, K (2011). Phylogenetic analysis of NS5B gene of classical swine fever virus isolates indicates plausible Chinese origin of Indian subgroup 2.2 viruses. Virus Genes 44: 104108.CrossRefGoogle ScholarPubMed
Paton, DJ, McGoldrick, A, Greiser-Wilke, I, Parchariyanon, S, Song, JY, Liou, PP, Stadejek, T, Lowings, JP, Bjorklund, H and Belak, S (2000). Genetic typing of classical swine fever virus. Veterinary Microbiology 73: 137157.CrossRefGoogle ScholarPubMed
Pereda, AJ, Greiser-Wilke, I, Schmitt, B, Rincon, MA, Mogollon, JD, Sabogal, ZY, Lora, AM, Sanguinetti, H and Piccone, ME (2005). Phylogenetic analysis of classical swine fever virus (CSFV) field isolates from outbreaks in South and Central America. Virus Research 110: 111118.CrossRefGoogle ScholarPubMed
Pol, F, Rossi, S, Mesplede, A, Kuntz-Simon, G and Le Potier, MF (2008). Two outbreaks of classical swine fever in wild boar in France. Veterinary Record 162: 811816.CrossRefGoogle ScholarPubMed
Postel, A, Schmeiser, S, Bernau, J, Meindl-Boehmer, A, Pridotkas, G, Dirbakova, Z, Mojzis, M and Becher, P (2012). Improved strategy for phylogenetic analysis of classical swine fever virus based on full-length E2 encoding sequences. Veterinary Research 43: 50.CrossRefGoogle ScholarPubMed
Postel, A, Jha, VC, Schmeiser, S and Becher, P (2013a). First molecular identification and characterization of classical swine fever virus isolates from Nepal. Archives of Virology 158: 207210.CrossRefGoogle ScholarPubMed
Postel, A, Schmeiser, S, Perera, CL, Rodriguez, LJ, Frias-Lepoureau, MT and Becher, P (2013b). Classical swine fever virus isolates from Cuba form a new subgenotype 1.4. Veterinary Microbiology 161: 334338.CrossRefGoogle Scholar
Rajkhowa, TK, Hauhnar, L, Lalrohlua, I and Mohanarao, GJ (2014). Emergence of 2.1. subgenotype of classical swine fever virus in pig population of India in 2011. Veterinary Quarterly 34: 224228.CrossRefGoogle ScholarPubMed
Risatti, GR, Borca, MV, Kutish, GF, Lu, Z, Holinka, LG, French, RA, Tulman, ER and Rock, DL (2005a). The E2 glycoprotein of classical swine fever virus is a virulence determinant in swine. Journal of Virology 79: 37873796.CrossRefGoogle ScholarPubMed
Risatti, GR, Holinka, LG, Lu, Z, Kutish, GF, Tulman, ER, French, RA, Sur, JH, Rock, DL and Borca, MV (2005b). Mutation of E1 glycoprotein of classical swine fever virus affects viral virulence in swine. Virology 343: 116127.CrossRefGoogle ScholarPubMed
Risatti, GR, Holinka, LG, Carrillo, C, Kutish, GF, Lu, Z, Tulman, ER, Sainz, IF and Borca, MV (2006). Identification of a novel virulence determinant within the E2 structural glycoprotein of classical swine fever virus. Virology 355: 94101.Google Scholar
Risatti, GR, Holinka, LG, Fernandez Sainz, I, Carrillo, C, Kutish, GF, Lu, Z, Zhu, J, Rock, DL and Borca, MV (2007a). Mutations in the carboxyl terminal region of E2 glycoprotein of classical swine fever virus are responsible for viral attenuation in swine. Virology 364: 371382.CrossRefGoogle ScholarPubMed
Risatti, GR, Holinka, LG, Fernandez Sainz, I, Carrillo, C, Lu, Z and Borca, MV (2007b). N-linked glycosylation status of classical swine fever virus strain Brescia E2 glycoprotein influences virulence in swine. Journal of Virology 81: 924933.CrossRefGoogle ScholarPubMed
Roychoudhury, P, Sarma, DK, Rajkhowa, S, Munir, M and Kuchipudi, SV (2014). Predominance of genotype 1.1 and emergence of genotype 2.2 classical swine fever viruses in north-eastern region of India. Transboundary and Emerging Disease 61 (suppl. 1): 6977.CrossRefGoogle ScholarPubMed
Ruggli, N, Summerfield, A, Fiebach, AR, Guzylack-Piriou, L, Bauhofer, O, Lamm, CG, Waltersperger, S, Matsuno, K, Liu, L, Gerber, M, Choi, KH, Hofmann, MA, Sakoda, Y and Tratschin, JD (2009). Classical swine fever virus can remain virulent after specific elimination of the interferon regulatory factor 3-degrading function of Npro. Journal of Virology 83: 817829.CrossRefGoogle ScholarPubMed
Rümenapf, T, Meyers, G, Stark, R and Thiel, HJ (1991). Molecular characterization of hog cholera virus. Archives of Virology 3: 718.CrossRefGoogle ScholarPubMed
Rümenapf, T, Unger, G, Strauss, JH and Thiel, HJ (1993). Processing of the envelope glycoproteins of pestiviruses. Journal of Virology 67: 32883294.CrossRefGoogle ScholarPubMed
Sainz, IF, Holinka, LG, Lu, Z, Risatti, GR and Borca, MV (2008). Removal of a N-linked glycosylation site of classical swine fever virus strain Brescia Erns glycoprotein affects virulence in swine. Virology 370: 122129.CrossRefGoogle ScholarPubMed
Sakoda, Y, Ozawa, S, Damrongwatanapokin, S, Sato, M, Ishikawa, K and Fukusho, A (1999). Genetic heterogeneity of porcine and ruminant pestiviruses mainly isolated in Japan. Veterinary Microbiology 65: 7586.Google Scholar
Sandvik, T, Crooke, H, Drew, TW, Blome, S, Greiser-Wilke, I, Moennig, V, Gous, TA, Gers, S, Kitching, JA, Buhrmann, G and Bruckner, GK (2005). Classical swine fever in South Africa after 87 years’ absence. Veterinary Record 157: 267.CrossRefGoogle ScholarPubMed
Sarma, DK, Mishra, N, Vilcek, S, Rajukumar, K, Behera, SP, Nema, RK, Dubey, P and Dubey, SC (2011). Phylogenetic analysis of recent classical swine fever virus (CSFV) isolates from Assam, India. Comparative Immunology, Microbiology and Infectious Disease 34: 1115.CrossRefGoogle ScholarPubMed
Shen, H, Pei, J, Bai, J, Zhao, M, Ju, C, Yi, L, Kang, Y, Zhang, X, Chen, L, Li, Y, Wang, J and Chen, J (2011). Genetic diversity and positive selection analysis of classical swine fever virus isolates in south China. Virus Genes 43: 234242.CrossRefGoogle ScholarPubMed
Simon, G, Le Dimna, M, Le Potier, MF and Pol, F (2013). Molecular tracing of classical swine fever viruses isolated from wild boars and pigs in France from 2002 to 2011. Veterinary Microbiology 166: 631638.CrossRefGoogle ScholarPubMed
Tamura, T, Nagashima, N, Ruggli, N, Summerfield, A, Kida, H and Sakoda, Y (2014). Npro of classical swine fever virus contributes to pathogenicity in pigs by preventing type I interferon induction at local replication sites. Veterinary Research 45: 47.CrossRefGoogle ScholarPubMed
Tamura, T, Sakoda, Y, Yoshino, F, Nomura, T, Yamamoto, N, Sato, Y, Okamatsu, M, Ruggli, N and Kida, H (2012). Selection of classical swine fever virus with enhanced pathogenicity reveals synergistic virulence determinants in E2 and NS4B. Journal of Virology 86: 86028613.CrossRefGoogle ScholarPubMed
Tang, F, Pan, Z and Zhang, C (2008). The selection pressure analysis of classical swine fever virus envelope protein genes Erns and E2. Virus Research 131: 132135.CrossRefGoogle ScholarPubMed
Tautz, N, Elbers, K, Stoll, D, Meyers, G and Thiel, HJ (1997). Serine protease of pestiviruses: determination of cleavage sites. Journal of Virology 71: 54155422.CrossRefGoogle ScholarPubMed
Tews, BA, Schurmann, EM and Meyers, G (2009). Mutation of cysteine 171 of pestivirus E rns RNase prevents homodimer formation and leads to attenuation of classical swine fever virus. Journal of Virology 83: 48234834.Google Scholar
Thiel, HJ, Stark, R, Weiland, E, Rümenapf, T and Meyers, G (1991). Hog cholera virus: molecular composition of virions from a pestivirus. Journal of Virology 65: 47054712.CrossRefGoogle ScholarPubMed
Töpfer, A, Höper, D, Blome, S, Beer, M, Beerenwinkel, N, Ruggli, N and Leifer, I (2013). Sequencing approach to analyze the role of quasispecies for classical swine fever. Virology 438: 1419.CrossRefGoogle ScholarPubMed
Tu, C, Lu, Z, Li, H, Yu, X, Liu, X, Li, Y, Zhang, H and Yin, Z (2001). Phylogenetic comparison of classical swine fever virus in China. Virus Research 81: 2937.CrossRefGoogle ScholarPubMed
Van Gennip, HG, Vlot, AC, Hulst, MM, De Smit, AJ and Moormann, RJ (2004). Determinants of virulence of classical swine fever virus strain Brescia. Journal of Virology 78: 88128823.CrossRefGoogle ScholarPubMed
Vlasova, A, Grebennikova, T, Zaberezhny, A, Greiser-Wilke, I, Floegel-Niesmann, G, Kurinnov, V, Aliper, T and Nepoklonov, E (2003). Molecular epidemiology of classical swine fever in the Russian Federation. Journal of Veterinary Medicine B Infectious Disease Veterianry Public Health 50: 363367.CrossRefGoogle ScholarPubMed
Wonnemann, H, Floegel-Niesmann, G, Moennig, V and Greiser-Wilke, I (2001). Genetic typing of German isolates of classical swine fever virus. Dtsch Tierarztl Wochenschr 108: 252256.Google ScholarPubMed
Wu, Z, Wang, Q, Feng, Q, Liu, Y, Teng, J, Yu, AC and Chen, J (2010). Correlation of the virulence of CSFV with evolutionary patterns of E2 glycoprotein. Frontiers in Bioscience (Elite Ed) 2: 204220.Google ScholarPubMed
Xu, J, Mendez, E, Caron, PR, Lin, C, Murcko, MA, Collett, MS and Rice, CM (1997). Bovine viral diarrhea virus NS3 serine proteinase: polyprotein cleavage sites, cofactor requirements, and molecular model of an enzyme essential for pestivirus replication. Journal of Virology 71: 53125322.CrossRefGoogle ScholarPubMed