Characterization of the E2 gene of classical swine fever virus (CSFV) isolated in Vietnam
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https://doi.org/10.15625/2615-9023/21702Keywords:
Classical swine fever virus, E2 gene, Epitope, genotypeAbstract
Classical swine fever is one of the most dangerous infectious diseases, causing significant economic damage to the pig industry globally and in Vietnam. The disease is caused by the Classical Swine Fever Virus (CSFV), an RNA virus with a high mutation rate. Classical swine fever remains a complex and persistent threat. In this study, the full E2 gene of CSFV strains collected from Ha Noi (21.028333 N, 105.853333 E), Da Nang (16.079 N, 108.217 E), and Quang Ninh (21.250982 N, 107.193604 E) was analyzed alongside three vaccine strains currently used in Vietnam. The results show that the highly virulent CSFV strains circulating in 2023 belong to genotypes 1.1, 2.1, and 2.2, while the vaccine strains in use belong to genotype 1.1. There are notable differences in amino acids at key antigen epitope sites between the vaccine strains and the circulating CSFV strains in 2023. These findings highlight the need to develop new vaccines that are better suited to the currently circulating virus strains.
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References
Beer M., Goller K. V., Staubach C., Blome S., 2015. Genetic variability and distribution of Classical swine fever virus. Animal health research reviews. 16(1): 33–39.
Bouma A., De Smit A. J., De Jong M. C., De Kluijver E. P., Moormann R. J., 2000. Determination of the onset of the herd-immunity induced by the E2 sub-unit vaccine against classical swine fever virus. Vaccine, 18(14): 1374–1381.
Chen N., Tong C., Li D., Wan J., Yuan X., Li X., Peng J., Fang W., 2010. Antigenic analysis of classical swine fever virus E2 glycoprotein using pig antibodies identifies residues contributing to antigenic variation of the vaccine C-strain and group 2 strains circulating in China. Virology Journal, 7: 1–14.
Deng M. C., Huang C. C., Huang T. S., Chang C. Y., Lin Y. J., Chien M. S., Jong M. H., 2005. Phylogenetic analysis of classical swine fever virus isolated from Taiwan. Veterinary microbiology, 106
(3–4): 187–193.
Edwards S., Fukusho A., Lefevre P. C., Lipowshi Z., Roeche P., 2000. Classical swine fever: the global situation. Veterinary Microbiology, 73: 103–109.
Hu D., Lv L., Gu J., Chen T., Xiao Y., Liu S., 2016. Genetic diversity and positive selection analysis of classical swine fever virus envelope protein gene E2 in East China under C-strain vaccination. Frontiers in microbiology, 7: 85.
Izzati U. Z., Hoa N. T., Lan N. T., Diep N. V., Fuke N., Hirai T., Yamaguchi R., 2021. Pathology of the outbreak of subgenotype 2.5 classical swine fever virus in northern Vietnam. Veterinary Medicine and Science, 7(1): 164–174.
Ji W., Niu D. D., Si H. L., Ding N. Z., He C.Q., 2014. Vaccination influences the evolution of classical swine fever virus. Infection, Genetics and Evolution, 25: 69–77.
Kamakawa A., Ho T. V., Yamada S., 2006. Epidemiological survey of viral diseases of pigs in the Mekong delta of Vietnam between 1999 and 2003. Veterinary Microbiology, 118(1-2): 47–56.
Luo Y., Li S., Sun Y., Qiu H. J., 2014. Classical swine fever in China: A minireview. Veterinary microbiology, 172(1–2): 1–6.
Meyers G., Thiel H. J., 1996. Molecular characterization of pestiviruses. Advances in virus research, 47: 58–118.
Nguyen Tien Dung., 2014. The reality and limitations in using vaccines to create immunity against swine fever. Journal of Veterinary Science and Technology, 21(6): 88–91 (In Vietnamese with summary in English).
OIE (2022) World Organisation for Animal Health. Chapter 3.9.3. Classical swine fever (infection with classical swine fever virus).
Paton D. J., McGoldrick A., Greiser-Wilke I., Parchariyanon S., Song J. Y., Liou P. P., Stadejek T., Lowings J. P., Bjorklund H., Belak S., 2000. Genetic typing of classical swine fever virus. Veterinary microbiology, 73(2-3): 137–157.
Qiu H. J., Shen R. X., Tong G. Z., 2006. The lapinized Chinese strain vaccine against classical swine fever virus: a retrospective review spanning half a century. Agricultural Sciences in China, 5(1): 1–14.
Sakoda Y., Ozawa S., Damrongwatanapokin S., Sato M., Ishikawa K., Fukusho A., 1999. Genetic heterogeneity of porcine and ruminant pestiviruses mainly isolated in Japan. Veterinary microbiology, 65(1): 75–86.
Tran Thi Dan, Luong Quy Phuong, Nguyen Ngoc Tuan, Thai Quoc Hieu, Nguyen Viet Nga, Ho Huynh Mai., 2009. Genetic analysis of the swine fever virus in Tien Giang province. Journal of veterinary science and technology, 16(2): 5–11 (In Vietnamese with English summary).
Thiel H. J., Stark R., Weiland E., Rumenapf T., Meyer G., 1991. Hog cholera virus: molecular composition of virions from a pestivirus. Journal of Virology, 65: 4705– 4712.
Tran D. H, Tran T. H, Pham T. N. M., Phung H. T. T., 2023. Rapid detection of classical swine fever virus (CSFV) by reverse-transcription loop-mediated isothermal amplification method (RT-LAMP). Journal of Science and Technololy Nguyen Tat Thanh Univ, 6: 22–28.
Van Oirschot J. T., 2003. Vaccinology of classical swine fever: from lab to field. Veterinary microbiology, 96: 367–384.
Xing C., Lu Z., Jiang J., Huang L., Xu J., He D., Wei Z., Huang H., Zhang H., Murong C., Tu C., Gong W., 2019. Sub-subgenotype 2.1c isolates of classical swine fever virus are dominant in Guangdong province of China, 2018. Infection, Genetics and Evolution, 68: 212–217.
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Copyright (c) 2025 Doan Thi Thanh Huong, Nguyen Thi Khue, Do Thi Roan, Nguyen Thi Thu Hien, Luu Minh Duc, Le Thi Hue, Pham Thi Khanh Linh, Le Thi Kim Xuyen, Doan Hai Ngan, Phan Xuan Doc
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