A novel and highly divergent Canine Distemper Virus lineage causing distemper in ferrets in Australia

Canine distemper virus (CDV) causes a highly contagious systemic infection in an array of animal species. In this study we report an outbreak of distemper in ferrets in two research facilities in Australia, caused by a novel lineage of CDV. While the CDV strain caused mainly mild symptoms in ferrets, histopathology results presented a typical profile of distemper pathology, with multi-system virus replication. Through the development of a discriminatory PCR, paired with full genome sequencing, we revealed that the outbreak was caused by a novel lineage of CDV. The novel CDV lineage was highly divergent, with less than 93% similarity across the H gene to other described lineages, including the vaccine strain, and diverged approximately 140–400 years ago. Enhanced surveillance to determine the prevalence of CDV in ferrets, dogs and other at-risk species is critical to better understand the presence and diversity of CDV in Australia currently. •Distemper outbreak in ferrets with moderate severity in two Australian animal research facilities.•Initial outbreak caused by novel, highly divergent lineage of CDV.•Better CDV surveillance of dogs, wild animals and feral animals in Australia is warranted.•This study reports the first full genome sequences of CDV from Australia.