Aloha MARMAM community,
On behalf of myself and my co-authors, I am pleased
to share our new publication titled "Targeted surveillance detected novel beaked whale circovirus in ten new host cetacean species across the Pacific basin."
Abstract:
The first cetacean circovirus, beaked whale circovirus (BWCV), was recently reported in a Longman’s beaked whale (Indopacetus pacificus)
stranded in Hawai‘i and represents an emergent disease with unknown
population impacts. In other species, circovirus infection may cause
mortality or opportunistic co-infection by other pathogens. We report on
a targeted surveillance of stranded cetaceans in the Pacific basin,
including archived beaked whale species, strandings where pathological
findings suggested disease presence, mass stranded animals, and
additional individuals to represent a broad range of Hawaiian cetacean
species. Archived tissues primarily from the brain, kidney, liver, lung,
spleen, and lymph nodes of individuals stranded between 2000 and 2020
(n=30) were tested by PCR for the presence of BWCV. Suspect positive
tissue amplicons were confirmed as BWCV through sequencing. Of the
screened individuals, 15 animals tested positive in one or more tissues,
with a single striped dolphin (Stenella coeruleoalba) testing
positive in all six tissues. The highest rate of detection among
positive cases was found in the brain (69%), followed by lymph (67%) and
lung tissues (64%). Additionally, co-infections of cetacean
morbillivirus (n=3), Brucella ceti (n=1), and Toxoplasma gondii
(n=1) were found among the positive cases. These results expand the
potential host range for BWCV into ten additional odontocete species.
New host species include a dwarf sperm whale (Kogia sima) that
stranded on O‘ahu in 2000, predating the initial case of BWCV. The
results broaden the known geographic range of BWCV to Saipan in the
Western Pacific, and American Samoa in the South Pacific, where stranded
Cuvier’s beaked whales (Ziphius cavirostris) tested positive.
Although the clinical significance is currently unknown, this study
demonstrates that BWCV has a high prevalence within targeted cetacean
screening efforts. Infectious diseases pose a major threat to cetaceans
and BWCV may represent an important emerging disease within populations
spanning the central, Western, and South Pacific.
Citation:
Clifton, C. W., Silva-Krott, I., Marsik, M. G., and West, K. L. (2023). Targeted surveillance detected novel beaked whale circovirus in ten new host cetacean species across the Pacific basin. Front. Mar. Sci. 9:945289. doi: 10.3389/fmars.2022.945289
Mahalo,
Cody
--
Cody Clifton
Graduate Research Assistant, PhD Student
Health and Stranding Lab
University of Hawaiʻi at Mānoa