Targeted surveillance detected novel beaked whale circovirus in ten new host cetacean species across the Pacific basin

The first cetacean circovirus, beaked whale circovirus (BWCV), was recently reported in a Longman’s ( Indopacetus pacificus ) stranded Hawai‘i and represents an emergent disease with unknown population impacts. In other species, infection may cause mortality or opportunistic co-infection by pathogens. We report on targeted surveillance of cetaceans the Pacific basin, including archived strandings where pathological findings suggested presence, mass animals, additional individuals to represent broad range Hawaiian species. Archived tissues primarily from brain, kidney, liver, lung, spleen, lymph nodes between 2000 2020 (n=30) were tested PCR for presence BWCV. Suspect positive tissue amplicons confirmed as BWCV through sequencing. Of screened individuals, 15 animals one more tissues, single striped dolphin Stenella coeruleoalba testing all six tissues. highest rate detection among cases found brain (69%), followed (67%) lung (64%). Additionally, co-infections morbillivirus (n=3), Brucella ceti (n=1), Toxoplasma gondii (n=1) cases. These results expand potential host into ten odontocete New species include dwarf sperm Kogia sima that O‘ahu 2000, predating initial case broaden known geographic Saipan Western Pacific, American Samoa South Cuvier’s whales Ziphius cavirostris positive. Although clinical significance is currently unknown, this study demonstrates has high prevalence within screening efforts. Infectious diseases pose major threat important emerging populations spanning central, Western, Pacific.