Transmission of morbilliviruses within and among marine mammal species

Transmission of morbilliviruses within and among marine mammal species has been documented in a variety of marine habitats. Cetacean morbillivirus spreads between cetacean species in the aquatic environment whereas both phocine distemper virus and canine distemper virus have been associated with transmission within and between pinniped and terrestrial carnivore species in their natural habitat and at the aquatic-terrestrial interface. Periodically these viruses have caused large epizootics involving thousands of animals, due to sustained intra-species virus transmission. Social behavior of host species, marine habitat, geographical barriers and virus host adaptations all likely contribute toward modulating virus spread. In combination with increased surveillance and whole genome sequencing, further research into ecological and host factors will be pivotal in better understanding the global transmission dynamics of marine morbilliviruses.