Background: Vaccination of farmed minks against canine distemper virus (CDV) has proved to be very effective. In the Netherlands, vaccination of farmed minks against CDV was mandatory until the closure of the local agricultural product boards at the end of 2014.

Objectives: To describe the first documented outbreaks of CD in Dutch mink farms since the closure of the agricultural product boards, as well as an outbreak in Belgium, with special attention to genotyping of the isolates.

Methods: A full post-mortem was performed on three carcasses per submission from farms A–C and on two carcasses from farm D. Molecular detection with subsequent typing was performed on eleven samples originating from four different farms. To assess genetic diversity partial sequences of the H gene of CDV were compared based on phylogenetic analysis.

Results: In 2017, there was a sudden series of CD outbreaks affecting four mink farms in the Netherlands (A–C) and Belgium (D). Gross, histologic and immunohistochemical findings were similar. There was a degree of genetic similarity between the viruses on farms A and D (98.5%) and between the viruses on farms B and C (97.3%), but the viruses from farms A and D belonged to a different clade than the viruses from farms B and C. Higher mortalities were reported in white and pastel minks.

Conclusions: Findings indicated that the difference in severity of the outbreaks was partially related to the genetic composition of the farm populations. Vaccination against CDV on Dutch and Belgian mink farms seems warranted.

背景：事实证明，对养殖的水貂进行犬瘟热疫苗（CDV）的疫苗接种非常有效。在荷兰，直到2014年底关闭当地农产品委员会之前，都必须对养殖水貂进行CDV疫苗接种。

目的：描述自农产品委员会关闭以来在荷兰水貂养殖场首次记录的CD暴发，以及比利时的暴发，特别注意分离株的基因分型。

方法：对来自A–C农场的每个屠体和来自D农场的两个屠体进行完整的验尸。对来自四个不同农场的11个样品进行了分子检测和随后的分型。为了评估遗传多样性，在系统发育分析的基础上比较了CDV H基因的部分序列。

结果： 2017年，突然爆发了一系列CD暴发，影响了荷兰（A–C）和比利时（D）的四个水貂养殖场。总体，组织学和免疫组化结果相似。A和D农场中的病毒之间（98.5％）以及B和C农场中的病毒（97.3％）之间存在一定程度的遗传相似性，但是A和D农场中的病毒与来自A和D农场的病毒属于不同的进化枝农场B和C。据报导，白色和淡色貂皮的死亡率更高。

结论：研究结果表明，暴发的严重程度差异与农场人口的遗传组成部分相关。似乎有必要在荷兰和比利时的貂皮农场进行CDV疫苗接种。