Research overview: receptor adaptation and the host jumps of canine distemper virus into felids

A central question in distemper ecology is how a virus historically associated with dogs repeatedly jumps into cats. This overview surveys research on the molecular basis of canine distemper virus host range, focusing on the receptors SLAM and nectin-4 and how mutations in the viral hemagglutinin can broaden tropism. It examines whether felid-affecting strains carry specific adaptations, how receptor compatibility shapes susceptibility across carnivore species, and what this implies for predicting future spillover. The synthesis links structural virology to field patterns of epidemic emergence in lions and tigers. It aims to help readers understand the mechanistic underpinnings of cross-species transmission, illustrating why distemper is such a successful multi-host pathogen and why small viral changes can have outsized consequences for wild cat populations.