Department of Parasitology and Animal Diseases, National Research Centre, 33 Bohouth Street, Dokki, Giza, 12622, Egypt.
Vet Res Commun. 2024 Dec;48(6):3921-3939. doi: 10.1007/s11259-024-10541-7. Epub 2024 Oct 8.
Lumpy skin disease (LSD) is a viral disease that affects cattle and buffaloes in Egypt, causing considerable economic losses in the animal sector. This study aimed to investigate the recent outbreak of LSDV in cattle and buffaloes and evaluate the potential role of the hard tick Rhipicephalus annulatus in their transmission through isolation and molecular characterization by multiplex PCR (mPCR) and real-time quantitative PCR (rt-qPCR) assays. A total of 50 skin biopsies (cattle n = 30, buffaloes n = 20), 110 nasal swabs (cattle n = 76, buffaloes n = 44), and 129 blood samples (cattle n = 84, buffaloes n = 45) were collected. In addition, 145 hard ticks of different stages were collected from cattle and buffaloes of different breeds and ages in different governorates in Egypt from November 2021 to June 2022. Multiplex PCR and real-time quantitative PCR (rt-qPCR) assays based on SYBR Green and targets (P32, VP32, G protein, and viral fusion protein) were used. We identified positive results in 17 out of 30 cattle skin biopsies (56.6%), 1 out of 7 buffalo skin scabs (14.3%), and 5 out of 45 buffalo blood samples (11.11%) using mPCR and RT-qPCR methods. We successfully isolated LSDV from hard ticks and cattle infested with ticks and exhibited characteristic signs of LSD on the chorioallantois membrane (CAM) of specific pathogen-free embryonated chicken eggs (SPF-ECE). The isolates were confirmed by multiplex PCR and RT-qPCR. The cyclic threshold (Ct) with correlation-slandered curve values of rt-qPCR ranging from 10.2 to 36.5 showed the amount of LSDV-DNA in different samples. The study's findings demonstrated the widespread circulation of LSDV in both cattle and buffaloes in Egypt and provided strong evidence that hard ticks R. annulatus play a role in the transmission of LSDV in susceptible animals.
绵羊痘与山羊痘（Lumpy skin disease，LSD）是一种影响埃及牛和水牛的病毒性疾病，给动物部门造成了巨大的经济损失。本研究旨在调查牛和水牛中 LSDV 的最新暴发情况，并通过多重聚合酶链反应（multiplex PCR，mPCR）和实时定量聚合酶链反应（real-time quantitative PCR，rt-qPCR）评估硬蜱 Rhpi-cephalus annulatus 在其传播中的潜在作用。共采集了 50 份皮肤活检（牛 30 份，水牛 20 份）、110 份鼻腔拭子（牛 76 份，水牛 44 份）和 129 份血液样本（牛 84 份，水牛 45 份）。此外，从 2021 年 11 月至 2022 年 6 月，在埃及不同省份的不同品种和不同年龄的牛和水牛中采集了 145 只不同发育阶段的硬蜱。采用基于 SYBR Green 和靶点（P32、VP32、G 蛋白和病毒融合蛋白）的多重 PCR 和实时定量 PCR（rt-qPCR）方法。mPCR 和 RT-qPCR 方法检测结果显示，30 份牛皮肤活检中有 17 份（56.6%）、7 份水牛皮肤结痂中有 1 份（14.3%）和 45 份水牛血液样本中有 5 份（11.11%）呈阳性。我们从感染蜱虫的牛和感染蜱虫的硬蜱中成功分离出 LSDV，并在无特定病原体的鸡胚（specific pathogen-free embryonated chicken eggs，SPF-ECE）的绒毛尿囊膜（chorioallantois membrane，CAM）上显示出 LSD 的特征性迹象。通过多重 PCR 和 RT-qPCR 对分离株进行了确认。rt-qPCR 的循环阈值（cycle threshold，Ct）与相关曲线值范围为 10.2 至 36.5，显示了不同样本中 LSDV-DNA 的含量。本研究结果表明，LSDV 在埃及的牛和水牛中广泛传播，并提供了有力证据表明硬蜱 Rhpi-cephalus annulatus 在易感动物中传播 LSDV 中发挥作用。
