Cetacean morbilliviruses have been documented to cause large epidemics in the North Atlantic Ocean and Mediterranean Sea but not in the North Pacific Ocean, and the reasons for this are unknown. A review of 212 strandings from 2000-2015 found nine animals with lesions compatible with morbillivirus infection, and 11 were tested via PCR. One striped dolphin was positive with a morbillivirus most closely related to two strains found in cetaceans in Hawaii. This study by Serrano and colleagues suggests that morbillivirus may be a rare contributor to mortality in cetaceans stranding along the California coast.
Serrano, L., Simeone, C.A., Colegrove, K.M., Duignan, P.J., Goldstein, T. and Gulland, F.M., 2017. Cetacean morbillivirus in odontocetes stranded along the central California coast, USA, 2000–15. Journal of Wildlife Diseases, 53(2), pp.386-392.