Housawi Fahdel M, Abuelzein Eltayb M, Gamee Ahmed A, Alafaleq Adel I
College of Veterinary Medicine and Animal Husbandry, King Faisal University.
Onderstepoort J Vet Res. 2012 Aug 7;79(1):E1-5. doi: 10.4102/ojvr.v79i1.397.
The epidemiology of orf virus infection in Saudi Arabia (SA) has been researched since 1990. The results obtained during this period indicate that the disease is widespread, has great economic impact and that no vaccine has been used against it. The present study compares the immunogenicity and protective efficacy of three locally developed live orf virus vaccines. Two of them differ in their passage history in Vero cell culture and the third was used as a virulent virus in glycerine buffer. To the best of the authors' knowledge, no similar comparative study has been conducted in the Middle East utilising three types of vaccines prepared from the same virus strain. Selection of the candidate seed orf virus and performance of the quality control tests were as laid out by the OIE for veterinary vaccine production. The vaccine seed virus was a field orf virus isolated from a previous orf outbreak in Saudi Arabia. A simple novel formula was developed to calculate the rate of reduction in the healing time (RHT %) in the challenged sheep. This allowed direct comparison of the efficacy of the three types of vaccines employed in the present study. The efficacy of each vaccine was tested on a cohort of local Noemi sheep.
自1990年以来，沙特阿拉伯（SA）对羊口疮病毒感染的流行病学进行了研究。在此期间获得的结果表明，该疾病广泛传播，具有巨大的经济影响，并且尚未使用疫苗来对抗它。本研究比较了三种本地开发的羊口疮病毒活疫苗的免疫原性和保护效力。其中两种在Vero细胞培养中的传代历史不同，第三种用作甘油缓冲液中的强毒病毒。据作者所知，中东地区尚未利用同一病毒株制备的三种疫苗进行类似的比较研究。候选种用羊口疮病毒的选择和质量控制测试的执行按照世界动物卫生组织（OIE）关于兽用疫苗生产的规定进行。疫苗种毒是从沙特阿拉伯先前的羊口疮疫情中分离出的一种田间羊口疮病毒。开发了一种简单的新公式来计算受攻击绵羊愈合时间的缩短率（RHT%）。这使得能够直接比较本研究中使用的三种疫苗的效力。每种疫苗的效力在一群当地的诺埃米绵羊上进行了测试。
