Haegeman A, Zro K, Sammin D, Vandenbussche F, Ennaji M M, De Clercq K
Viral Diseases, Vesicular and Exotic Diseases, CODA-CERVA, Brussels, Belgium.
Laboratoire de Virologie et Hygiène & Microbiologie, Faculté des Sciences et Techniques, Mohammedia, Morocco.
Transbound Emerg Dis. 2016 Dec;63(6):e278-e287. doi: 10.1111/tbed.12342. Epub 2015 Mar 9.
Sheep pox is endemic in most parts of Northern Africa and has the potential to cause severe economic problems. Live attenuated vaccines are used in Morocco, and in many other countries, to control the disease. Sheep pox virus (SPPV) re-appeared in 2010 causing a nodular clinical form previously not observed in Morocco. The severe clinical signs observed during the course of this outbreak and initial reports citing similarity in nucleotide sequence between the Moroccan vaccine strain and field isolates warranted a more in depth analysis of this epizootic. In this study, sequence analysis showed that isolates obtained from four provinces of eastern Morocco were identical, demonstrating that a single SPPV strain was responsible for the 2010 epizootic. In addition, the genome fragments sequenced and phylogenetic analyses undertaken as part of this study showed significant differences between field isolates and the Moroccan vaccine strain. New PCR methods were developed to differentiate between wild-type isolates and vaccine strains of SPPV. Using these methods, no trace of wild-type SPPV was found in the vaccine and no evidence was found to suggest that the vaccine strain was causing clinical disease.
绵羊痘在北非大部分地区呈地方流行性，有可能引发严重的经济问题。摩洛哥和许多其他国家使用减毒活疫苗来控制该病。绵羊痘病毒（SPPV）于2010年再次出现，引发了一种摩洛哥此前未见过的结节性临床症状。此次疫情期间观察到的严重临床症状以及初步报告称摩洛哥疫苗株与野外分离株在核苷酸序列上具有相似性，这使得有必要对此次动物疫病流行进行更深入的分析。在本研究中，序列分析表明，从摩洛哥东部四个省份获得的分离株是相同的，这表明单一的SPPV毒株导致了2010年的动物疫病流行。此外，作为本研究一部分进行的基因组片段测序和系统发育分析表明，野外分离株与摩洛哥疫苗株之间存在显著差异。开发了新的PCR方法来区分SPPV的野生型分离株和疫苗株。使用这些方法，在疫苗中未发现野生型SPPV的踪迹，也没有证据表明疫苗株正在引发临床疾病。
