Wachendörfer G, Frost J W, Gutmann B, Hofmann J, Schneider L G, Eskens U, Dingeldein W
Tierarztl Prax. 1986;14(2):185-96.
Since spring 1983 a field trial to immunize foxes by the oral route against rabies has been carried out in a heavily infected area of Hessen measuring about 1,500 km2. The vaccine strain SAD B 19, produced by the Federal Research Institute for Animal Virus Diseases at Tübingen and filled into 2 ml aliquots, was inserted into chicken heads and distributed by forest rangers in the trial area, 15 baits per km2. Up to the present day five baiting campaigns, two per year in spring and autumn, have been completed and in all 110,000 vaccine baits additionally marked with 150 mg tetracycline were layed out. Four baitings have been previously evaluated. With the exception of some rabies cases on the border to the unvaccinated region in the northwest, rabies was reduced impressively. A secondary outbreak in the region of Hausen/Kiedrich, caused by an extremely high density of the fox population, was eradicated by increasing the baits to 25 per km2. The number of rabies cases, which amounted to 238 within 15 months prior to the vaccination trial, went down from 38 in the first 6 months to 6 cases after the fourth baiting. As innocuity control 2,273 wild and domestic animals from the vaccination area were examined for the presence of the vaccine virus. The results were always negative indicating that rabies strain SAD B 19 had not established an infective cycle in wildlife. As could be shown by the marker studies, an average of 78 per cent of the foxes (variation of the baitings from 62 per cent to 82 per cent) had taken up one or more baits. Seroconversion had been achieved in 65 per cent of the foxes (variation from 43 per cent to 70 per cent) as demonstrated by the presence of neutralizing antibodies. From experiences in Switzerland it can be expected, that rabies will be extinguished, if 50 per cent of the population are successfully immunized. This value has been surpassed in the field trial in Hessen. These very promising results have led to the project of an enlargement of the vaccination area to 12,000 km2. The neighbouring states of Rheinland-Pfalz and Nordrhein-Westfalen have joined in this effort, which has started in autumn 1985 with a new artificial vaccine bait developed at the Tübingen research institute.
自1983年春季起，在黑森州一个面积约1500平方公里、狂犬病感染严重的地区开展了一项通过口服途径对狐狸进行狂犬病免疫的田间试验。由图宾根联邦动物病毒病研究所生产、灌装成2毫升分装的疫苗毒株SAD B 19，被植入鸡头，由护林员在试验区分发，每平方公里投放15个诱饵。截至目前，已完成了五次诱饵投放行动，每年春秋各两次，总共投放了110,000个额外添加了150毫克四环素的疫苗诱饵。此前已对四次诱饵投放进行了评估。除了西北部未接种疫苗地区边界出现的一些狂犬病病例外，狂犬病感染情况显著减少。豪森/基德里希地区因狐狸种群密度极高引发的二次疫情，通过将诱饵增加到每平方公里25个得以根除。在疫苗接种试验前15个月内狂犬病病例达238例，在第一次诱饵投放后的头6个月降至38例，在第四次诱饵投放后降至6例。作为安全性控制，对来自接种区的2273只野生动物和家畜进行了疫苗病毒检测。结果均为阴性，表明狂犬病毒株SAD B 19在野生动物中未形成感染循环。标记研究表明，平均78%的狐狸（诱饵投放比例在62%至82%之间变化）摄取了一个或多个诱饵。中和抗体的存在证明，65%的狐狸（比例在43%至70%之间变化）实现了血清转化。根据瑞士的经验，可以预期，如果50%的种群成功免疫，狂犬病将被根除。这一数值在黑森州的田间试验中已被超越。这些非常有前景的结果促使开展了将接种区扩大到12000平方公里的项目。莱茵兰 - 普法尔茨州和北莱茵 - 威斯特法伦州这两个邻国已参与此项工作，该工作于1985年秋季启动，采用了图宾根研究所研发的新型人工疫苗诱饵。
