Cytoplasmic inclusions were also present in bronchiolar epithelium and in the urinary bladder mucosa. Severe bronchopneumonia was also present. The host range of canine distemper virus includes the dog, coyote, fox, wolf, dingo, jackal, raccoon, panda, weasel, mink, ferret, badger, skunk and otter. It was felt that raccoons may have transmitted the infection to mink in this case. A similar, if not identical virus, has been reported to cause distemper-like illness in captive and wild leopards, tigers, lions, jaguars and civets.
Similar viruses infect harbor seals, porpoises and javelinas.
Infection with CDV occurs by inhalation with the virus localizing in tonsils and bronchial lymph nodes. After 2-5 days there is a cell associated viremia, with the virus infecting lymph nodes, spleen, thymus, bone marrow, and macrophages in the lamina propria of the stomach and intestine. At this stage of infection, severe depletion of lymphocytes may develop with concomitant immunosuppression. The brain is sometimes affected, usually after the visceral infection has ended. The virus first infects macrophages in the meninges and later spreads to ependymal cells, glial cells, and neurons.