Jacobs L, Mulder W, Dercksen D, Vos J, Raymakers R, Kimman T
Institute for Animal Science and Health (ID-DLO), Lelystad, The Netherlands.
Res Vet Sci. 1997 May-Jun;62(3):271-4. doi: 10.1016/s0034-5288(97)90203-4.
An outbreak of Aujeszky's disease occurred in a flock of sheep which had been housed together with pigs. After the death of five sheep with clinical signs of Aujeszky's disease, the remaining sheep were vaccinated with the Bartha vaccine strain, and the pigs were vaccinated with the 783 vaccine strain of Aujeszky's disease virus. Despite vaccination, however, more sheep died. Brain tissues from four sheep were collected for virus isolation and for immunohistological examinations. Only vaccine virus (gE-negative) was detected in the tissue. After DNA restriction enzyme analysis of the isolated virus, DNA of one or both of the vaccine strains was detected in all sheep. In one sheep field virus DNA was also detected. However, when the polymerase chain reaction was performed on samples prepared from paraffin-embedded tissues, DNA of field virus (gE-positive) was detected in all four sheep. It was probable that the sheep had not yet mounted a sufficient immune response to the vaccine virus, or were already infected with field virus at the time of vaccination. We concluded that the sheep died from field virus infection and not from vaccine virus infection and that only the polymerase chain reaction made it possible to specifically detect even very small amounts of field virus DNA among vaccine virus DNA in all investigated sheep.
一群与猪混养的绵羊中发生了奥耶斯基氏病疫情。在5只出现奥耶斯基氏病临床症状的绵羊死亡后，其余绵羊接种了巴塔疫苗株，猪则接种了奥耶斯基氏病病毒783疫苗株。然而，尽管进行了疫苗接种，仍有更多绵羊死亡。采集了4只绵羊的脑组织用于病毒分离和免疫组织学检查。在组织中仅检测到疫苗病毒（gE阴性）。对分离出的病毒进行DNA限制性内切酶分析后，在所有绵羊中均检测到一种或两种疫苗株的DNA。在一个绵羊场还检测到了野毒DNA。然而，当对石蜡包埋组织制备的样本进行聚合酶链反应时，在所有4只绵羊中均检测到了野毒（gE阳性）DNA。很可能这些绵羊对疫苗病毒尚未产生足够的免疫反应，或者在接种疫苗时已经感染了野毒。我们得出结论，绵羊死于野毒感染而非疫苗病毒感染，并且只有聚合酶链反应能够在所有调查的绵羊中，在疫苗病毒DNA中特异性地检测到即使是极少量的野毒DNA。
