Quan M, Murphy C M, Zhang Z, Alexandersen S
Pirbright Laboratory, Institute for Animal Health, Ash Rd, Woking, Surrey GU24 0NF, UK.
J Comp Pathol. 2004 Nov;131(4):294-307. doi: 10.1016/j.jcpa.2004.05.002.
This paper provides a quantitative description of the early infectious process in pigs experimentally infected with foot-and-mouth disease virus (FMDV), obtained by dose-dependent, time course studies of viral load in serum. Pigs were inoculated by the intravenous or intradermal/subcutaneous route with FMDV and housed together in groups or individually. The effects of dose, inoculation route and exposure intensity on the replication of FMDV in vivo and the development of disease were studied. It was shown that the higher the dose, the shorter was the time to the start of active viraemia and to the onset of clinical signs. Exposure intensity and housing conditions influenced the viral dynamics of FMDV. Increasing the exposure intensity, by increasing the number of infected pigs housed together, had the effect of synchronizing the infection and reducing the variance in the start of active viraemia. Increasing the number of pigs housed together also increased the interaction between the pigs and the activity of individual pigs, which had the effect of shortening the time to the onset of clinical signs such as vesicle formation. Intradermal inoculation was more effective than intravenous inoculation for transmitting FMDV to pigs, resulting in shorter times to the start of active viraemia and in higher clinical scores.
本文通过对血清中病毒载量进行剂量依赖性、时间进程研究，定量描述了实验感染口蹄疫病毒（FMDV）的猪的早期感染过程。猪通过静脉或皮内/皮下途径接种FMDV，并成群或单独饲养。研究了剂量、接种途径和暴露强度对口蹄疫病毒在体内复制及疾病发展的影响。结果表明，剂量越高，出现活跃病毒血症开始的时间和临床症状出现的时间越短。暴露强度和饲养条件影响口蹄疫病毒的病毒动态。通过增加共同饲养的感染猪数量来提高暴露强度，具有使感染同步化并减少活跃病毒血症开始时间差异的作用。增加共同饲养的猪的数量也增加了猪之间的相互作用以及个体猪的活动，这具有缩短出现如水疱形成等临床症状时间的作用。皮内接种比静脉接种在将口蹄疫病毒传播给猪方面更有效，导致出现活跃病毒血症开始的时间更短且临床评分更高。
