Abstract：
Virulent Rhodococcus equi strains expressing virulence-associated 15-17 kDa protein (VapA) and having a large virulence plasmid (pVAPA) of 85-90 kb containing vapA gene are pathogenic for horses. In the last two decades, following pVAPA, two host-associated virulence plasmid types of R. equi have been discovered: a circular plasmid, pVAPB, associated with porcine isolates in 1995, and a recently detected linear plasmid, pVAPN, related to bovine and caprine isolates. Molecular epidemiological studies of R. equi infection in foals on horse-breeding farms in Japan and many countries around the world have been conducted in the last three decades, and the epidemiological studies using restriction enzyme digestion patterns of plasmid DNAs from virulent isolates have shown 14 distinct pVAPA subtypes and their geographical preference. This short review summarizes previous reports regarding equine-associated pVAPA subtypes in the world and discusses their geographic distribution from the standpoint of horse movements.
摘要：
表达毒力相关的15-17kDa蛋白（VapA）并具有包含vapA基因的85-90kb的大毒力质粒（pVAPA）的强力马红球菌菌株对马具有致病性。在过去的二十年里，在pVAPA之后，已经发现了两种与宿主相关的R.equi毒力质粒类型：环状质粒，pVAPB,与1995年的猪分离株有关，以及最近检测到的线性质粒，pVAPN,与牛和山羊分离株有关。在过去的三十年中，已经对日本和世界上许多国家的种马场马驹中马驹的R.equi感染进行了分子流行病学研究，使用毒力分离株的质粒DNA的限制性内切酶消化模式进行的流行病学研究显示，有14种不同的pVAPA亚型及其地理偏好。这篇简短的评论总结了以前关于世界上与马相关的pVAPA亚型的报道，并从马运动的角度讨论了它们的地理分布。
