Department Discovery & Technology, MSD Animal Health, Wim de Körverstraat 35, P.O. Box 31, 5830 AA Boxmeer, The Netherlands.
Department R&D-IT, MSD Animal Health, Wim de Körverstraat 35, P.O. Box 31, 5830 AA Boxmeer, The Netherlands.
Genes (Basel). 2024 Feb 20;15(3):264. doi: 10.3390/genes15030264.
In 2015 and 2016, two Barramundi () farms in Singapore reported a disease outbreak characterized by lethargic behavior, pronounced inappetence, generalized skin lesions, erosions of the fins and tail, and ultimately high mortality in their fish. Next-generation sequencing and PCR confirmed presence of a novel virus belonging to the family, herpesvirus (LCHV), which was subsequently isolated and cultured. We characterize, for the first time, the complete genome of two cultured LCHV isolates. The genome contains a long unique region of approximately 105,000 bp flanked by terminal repeats of approximately 24,800 bp, of which the first 8.2 kb do not show any similarity to described genomes in the family. The two cultured isolates share 89% nucleotide identity, and their closest relatives are the viruses belonging to the genus . Experimental infections using one of the cultured LCHV isolates resulted in identical clinical signs as originally described in the index farm, both in intraperitoneal-injection infected fish and cohabitant fish, with mortality in both groups. Histopathological analysis showed pronounced abnormalities in the gills. Virus culture and PCR analysis confirmed the replication of LCHV in the infected fish, and thus Koch's postulates were fulfilled.
2015 年和 2016 年，新加坡的两家金目鲈养殖场报告了一种疾病爆发，其特征为行为迟缓、明显厌食、全身皮肤病变、鳍和尾溃烂，最终导致鱼类死亡率高。下一代测序和 PCR 证实存在一种新型病毒，属于疱疹病毒科，随后分离并培养了该病毒。我们首次对两种培养的 LCHV 分离株的完整基因组进行了描述。基因组包含一个约 105000 bp 的长独特区域，两侧是约 24800 bp 的末端重复序列，其中前 8.2 kb 与疱疹病毒科中描述的基因组没有任何相似性。两种培养的分离株核苷酸同一性为 89%，它们最接近的亲缘关系是属于. 使用其中一种培养的 LCHV 分离株进行的实验感染导致与最初在索引养殖场中描述的相同的临床症状，无论是在腹腔注射感染的鱼还是同居鱼中，两组都有死亡率。组织病理学分析显示鳃有明显的异常。病毒培养和 PCR 分析证实 LCHV 在感染的鱼中复制，因此满足了科赫假设。
