A joint research paper with Nihon University showing that cetacean morbillivirus is also spreading in the seas around Japan has been published in Microbiology and Immunology.

https://onlinelibrary.wiley.com/doi/epdf/10.1111/1348-0421.13207

Kaede Tashiro et al. Serological evidence of cetacean morbillivirus infection in common bottlenose dolphins in Japan

Our research has revealed that approximately 40% of wild dolphins born in the seas around Japan have neutralizing antibodies against the cetacean morbillivirus. This finding suggests that cetacean morbillivirus infection is spreading widely among wild dolphins in the seas around Japan without any noticeable outbreaks or mass dolphin deaths, and that it remains undetected.