Masson E, Bruyère-Masson V, Vuillaume P, Lemoyne S, Aubert M
Laboratoire d'études sur la rage et la pathologie des animaux sauvages, AFSSA Nancy, Malzéville, France.
Vet Res. 1999 Nov-Dec;30(6):595-605.
The vaccination of foxes by distributing vaccine baits in the environment was initiated in France in 1986. Two campaigns per year were carried out: one in the spring and one in the autumn. After the spring campaigns, only 22-52% of fox cubs consumed vaccine baits compared to 75% of the adults and 70-80% of the adults or fox cubs after autumn campaigns. In order to reduce the period of time during which fox cubs do not have access to baits and are not immunised, a vaccination campaign was organised during the summer of 1992 over a contaminated area of 25,748 km2 where vaccines had never previously been given. Vaccine bait stability was assessed during the same summer in the field and their appetence tested on captive foxes. The efficacy of the campaign was evaluated by the relative decrease in rabies incidence and the rate of bait uptake by foxes compared to those from neighbouring areas vaccinated for the first time with the same vaccine during the spring or autumn. Summer vaccination significantly increased (P < 0.01) bait uptake by fox cubs (71%) compared with spring vaccination (39%), but no significant difference was observed for adult foxes. Moreover, the decrease in rabies incidence, measured during the 6-month period following the campaigns was less pronounced after summer vaccination (49% decrease) than when the first vaccination was carried out during the spring or autumn (79 and 72% decrease, respectively). Three campaigns led to an apparent elimination of rabies when the first campaign was performed in the spring or autumn, but only to a 76% decrease in rabies incidence density index when the first campaign was performed during the summer. The high thermostability of the Raboral VRG bait permits its use during the summer for an emergency campaign. For routine vaccination plans, however, the classical calendar of spring and autumn vaccination campaigns should continue to be preferred.
1986年法国开始通过在环境中投放疫苗诱饵对狐狸进行疫苗接种。每年开展两次活动：一次在春季，一次在秋季。春季活动后，只有22% - 52%的幼狐食用疫苗诱饵，而成狐的这一比例为75%，秋季活动后成年狐狸或幼狐的这一比例为70% - 80%。为了缩短幼狐无法获取诱饵且未接种疫苗的时间，1992年夏季在一个面积为25748平方公里的曾未接种过疫苗的污染区域组织了一次疫苗接种活动。同年夏季在野外评估了疫苗诱饵的稳定性，并在圈养狐狸身上测试了它们的适口性。与春季或秋季首次使用相同疫苗进行接种的邻近地区相比，通过狂犬病发病率的相对下降以及狐狸对诱饵的摄取率来评估此次活动的效果。与春季接种（39%）相比，夏季接种显著提高了（P < 0.01）幼狐对诱饵的摄取率（71%），但成年狐狸未观察到显著差异。此外，在活动后的6个月期间测量的狂犬病发病率下降情况，夏季接种后（下降49%）不如春季或秋季首次接种时明显（分别下降79%和72%）。当首次活动在春季或秋季进行时，三次活动导致狂犬病明显消除，但当首次活动在夏季进行时，狂犬病发病率密度指数仅下降了76%。Raboral VRG诱饵的高热稳定性使其可在夏季用于应急活动。然而，对于常规疫苗接种计划，春季和秋季疫苗接种活动的传统日程仍应继续优先采用。
