Canine distemper virus and multiple sclerosis: A real or an anecdotal association?

Canine distemper virus (CDV) has been postulated to play a role in multiple sclerosis (MS), primarily on the basis of epidemiological evidence that has never been confirmed. However, this anecdotal association is still made by physicians and veterinarians. Although morbilliviruses such as CDV and measles virus (MV) potentially use the same cell surface receptor, CDV and others animal morbilliviruses have not yet been definitively implicated in any human disease. In this mini-review, the suggested but unproven involvement of CDV in MS will be addressed, and a possible explanation for the lack of CDV zoonotic infection will also be briefly discussed. The relationship between CDV infection and the development of demyelinating lesions will be revised because distemper is a disease associated with naturally occurring demyelinating encephalomyelitis, and the pathogenesis of distemper-related demyelination has been used for the study of demyelinating conditions in humans. Additionally, distemper-related demyelinating encephalitis shares important neuropathological aspects with MS.