Bamouh Zohra, Hamdi Jihane, Elkarhat Zouhair, Kichou Faouzi, Fellahi Siham, Watts Doug M, Elharrak Mehdi
Research and Development, MCI Santé Animale, Lot. 157, Z. I., Sud-Ouest (ERAC) B.P: 278, Mohammedia, 28810, Morocco; Hassan II Agronomic and Veterinary Institute, Rabat, Morocco.
Research and Development, MCI Santé Animale, Lot. 157, Z. I., Sud-Ouest (ERAC) B.P: 278, Mohammedia, 28810, Morocco.
Microb Pathog. 2025 Jan;198:107130. doi: 10.1016/j.micpath.2024.107130. Epub 2024 Nov 17.
Camel contagious ecthyma is a highly infectious viral skin disease that affects camels and causes economic losses. This study reports the isolation and the phylogenetic analysis of contagious ecthyma virus among camels in Morocco. The disease was detected in four among fifteen camels with severe papules on the lips and nares. Samples of skin crusts were collected and pooled for virus isolation and titration, PCR testing, and histopathological examination. PCR was used to amplify the B2L gene and the resulting product was sequenced and analyzed genetically. The study's findings indicate the presence of characteristic microscopic changes of poxvirus infection in the examined tissues and the virus was isolated on two cells (lambs testis and Vero) and showed distinct growth patterns. The virus grew rapidly on TA cells and delayed growth on Vero cells. The third passage showed cytopathic effects characterized by cell aggregation. Sequence analysis of the B2L gene revealed 100 % similarity to the camel contagious Ecthyma virus isolated from Ethiopia. The camel virus isolates can be classified into two genetic clades according to the B2L gene sequence: the Asian lineage, which includes isolates from Saudi Arabia, Bahrain, and India, and the African lineage, which includes isolates from the Sudan. In conclusion, this is the first instance of the camel contagious ecthyma virus being identified in North Africa in a herd of camels following exposure to stress. Moreover, the progression of the disease was closely monitored from onset to recovery in a setting without the bacterial complication often observed in the field. The virus exhibited opportunistic behavior, exploiting the stress response. Further studies are warranted to evaluate the pathogenicity of the virus in camels and to genetically characterize the circulating virus from different regions. This will be highly beneficial in the development of an appropriate vaccine.
骆驼传染性脓疱性皮炎是一种具有高度传染性的病毒性皮肤病，会感染骆驼并造成经济损失。本研究报告了摩洛哥骆驼中传染性脓疱性皮炎病毒的分离及系统发育分析。在15头骆驼中有4头被检测出患有该病，这些骆驼的嘴唇和鼻孔处出现严重丘疹。采集皮肤结痂样本并合并用于病毒分离和滴定、聚合酶链反应（PCR）检测以及组织病理学检查。使用PCR扩增B2L基因，对所得产物进行测序并进行基因分析。研究结果表明，在检查的组织中存在痘病毒感染的特征性微观变化，该病毒在两种细胞（羔羊睾丸细胞和非洲绿猴肾细胞）上分离出来，并呈现出不同的生长模式。该病毒在TA细胞上生长迅速，在非洲绿猴肾细胞上生长延迟。第三代传代表现出以细胞聚集为特征的细胞病变效应。B2L基因的序列分析显示，其与从埃塞俄比亚分离出的骆驼传染性脓疱性皮炎病毒有100%的相似性。根据B2L基因序列，骆驼病毒分离株可分为两个遗传分支：亚洲分支，包括来自沙特阿拉伯、巴林和印度的分离株；非洲分支，包括来自苏丹的分离株。总之，这是首次在北非一群骆驼中发现骆驼传染性脓疱性皮炎病毒，这些骆驼此前经历了应激。此外，在没有实地常见细菌并发症的情况下，对疾病从发病到康复的过程进行了密切监测。该病毒表现出机会主义行为，利用了应激反应。有必要进一步开展研究，以评估该病毒在骆驼中的致病性，并对来自不同地区的流行病毒进行基因特征分析。这对于开发合适的疫苗将非常有益。
