Federal Centre for Animal Health, Vladimir, 600901, Russia.
Department of Pathobiological Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA, 70803, USA.
Mol Biol Rep. 2024 Sep 25;51(1):1011. doi: 10.1007/s11033-024-09961-0.
African swine fever (ASF) is a contagious viral disease that affects pigs and wild boars, with a mortality rate of up to 100% in susceptible animals. The virus has been circulating in Europe and Asia since its introduction in 2007. Initially, all studied isolates were identified as genotype II, but in 2021 genotype I was reported in China. Later in 2023, the first recombinant virus of genotype I and II was identified in China, with an isolate dating back to 2021, this was followed by the detection of 6 recombinant isolates in Vietnam.
In this study, an ASFV isolate from the Primorsky Region of Russia obtained from a domestic pig was analyzed by sequencing several genome markers as well as the full genome. Eight pigs were infected with the isolate to assess its virulence.
Virus replication in cell culture showed hemadsorption, while sequencing of genome markers clustered the isolate into both genotype I and genotype II. The whole-genome sequence showed that the Russian isolate shared a 99.99% identity with recombinant isolates described earlier in China. Experimental animals developed ASF disease after the introduction of a low dose of the virus (10 HAU50) and died within 7 days post-infection, presenting an acute form of the disease.
This is the first report on recombinant ASFV in Russia's territory. The results once again confirm the transboundary nature of the disease, demonstrating the vulnerability of the global pig industry underscoring the need for developing new ASF vaccines effective against recombinant strains and emphasizing the importance of continuous molecular monitoring to detect emerging threats promptly.
非洲猪瘟（ASF）是一种传染性病毒病，会影响猪和野猪，易感动物的死亡率高达 100%。该病毒自 2007 年传入以来一直在欧洲和亚洲传播。最初，所有研究的分离株均被鉴定为基因型 II，但 2021 年在中国报告了基因型 I。随后在 2023 年，中国首次鉴定出基因型 I 和 II 的重组病毒，分离株可追溯到 2021 年，随后在越南检测到 6 个重组分离株。
在这项研究中，分析了来自俄罗斯滨海边疆区的一个 ASF 分离株，该分离株是从一头家猪中获得的，通过对几个基因组标记以及全基因组进行测序来分析。用该分离株感染了 8 头猪，以评估其毒力。
病毒在细胞培养中的复制表现出血凝作用，而基因组标记的测序将该分离株聚类为基因型 I 和基因型 II。全基因组序列显示，俄罗斯分离株与中国早期描述的重组分离株具有 99.99%的同源性。实验动物在接种低剂量病毒（10 HAU50）后发展为 ASF 疾病，并在感染后 7 天内死亡，呈现出疾病的急性形式。
这是俄罗斯领土上首例重组 ASF 的报告。结果再次证实了该疾病的跨界性质，表明全球养猪业的脆弱性，强调了开发针对重组株有效的新型 ASF 疫苗的必要性，并强调了持续进行分子监测以及时发现新出现的威胁的重要性。
