Institute of Veterinary, Animal and Biomedical Sciences, Private Bag 11 222, Massey University, Palmerston North, New Zealand.
Vet Microbiol. 2011 Aug 26;152(1-2):176-80. doi: 10.1016/j.vetmic.2011.04.017. Epub 2011 Apr 22.
The significance of infection with Equid herpesvirus 2 (EHV-2) remains unresolved, mainly due to its widespread distribution, and frequent isolation of the virus not only from diseased animals, but also from clinically normal horses. It has been suggested that EHV-2 exerts its effects on the host indirectly, through predisposition to secondary infections. The aim of this study was to determine kinetics of EHV-2 infection among foals and to investigate the role that EHV-2 may play in development of Rhodococcus equi pneumonia on one farm. Serial blood samples were collected from 43 foals over a period of 10 months. Viral load of EHV-2 in blood was determined using quantitative realtime PCR assay. All but 2 foals were positive for EHV-2 on at least one occasion. The majority (88%) of foals became infected with EHV-2 within the first 2 months of life. Once infected, most foals (86%) remained positive for EHV-2 on all subsequent samplings. The load of EHV-2 varied between individual foals and between different sampling times for each foal. There was a significant difference in EHV-2 load between samples collected from healthy foals and foals suspected of R. equi pneumonia only for 2-month-old foals, but not for foals of other ages. The results of this study extend our knowledge of EHV-2 epidemiology among foals.
马疱疹病毒 2 型（EHV-2）感染的意义仍未得到解决，主要是因为它广泛分布，而且该病毒不仅经常从患病动物中分离出来，也经常从临床正常的马中分离出来。有人认为 EHV-2 通过对继发感染的易感性，间接地对宿主产生影响。本研究的目的是确定幼驹中 EHV-2 感染的动力学，并研究 EHV-2 在一个农场中罗得西亚放线菌肺炎发展中可能起的作用。在 10 个月的时间里，从 43 匹幼驹中采集了一系列血液样本。使用定量实时 PCR 检测法测定血液中 EHV-2 的病毒载量。除了 2 匹幼驹外，所有幼驹至少有一次 EHV-2 呈阳性。大多数（88%）幼驹在生命的头 2 个月内感染了 EHV-2。一旦感染，大多数幼驹（86%）在随后的所有采样中都对 EHV-2 呈阳性。EHV-2 的载量在个体幼驹之间以及每个幼驹的不同采样时间之间有所不同。仅对于 2 月龄的幼驹，在从健康幼驹和疑似罗得西亚放线菌肺炎的幼驹中采集的样本之间，EHV-2 载量存在显著差异，但对于其他年龄的幼驹则没有。本研究的结果扩展了我们对幼驹中 EHV-2 流行病学的认识。
