Phylogenomic Diversity of Cetacean Morbilliviruses
Nelmarie Landrau-Giovannetti1*+; Lauren Brown1; Rachel Henríquez1; Linda L. Archer1; Galaxia Cortés-Hinojosa1; José Luiz Catão-Dias2; Pádraig J. Duignan3; Kátia R. Groch2; Ole Nielsen4; Teresa K. Rowles5; Jeremiah T. Saliki6; Nahiid Stephens7; Jianning Wang8; Kristi West9; James F.X. Wellehan1; Thomas D. Waltzek1
1College of Veterinary Medicine, University of Florida, Gainesville, FL, USA; 2Department of Pathology, School of Veterinary Medicine and Animal Science, University of São Paulo, Brazil; 3Department of Ecosystem and Public Health, University of Calgary, Calgary, AB, Canada; 4Department of Fisheries and Oceans Canada, Central and Arctic Region, Winnipeg, MB, Canada; 5National Marine Fisheries Service, Marine Mammal Health and Stranding Response Program, Silver Spring, MD, USA; 6Athens Veterinary Diagnostic Laboratory, College of Veterinary Medicine, University of Georgia, Athens, GA, USA; 7School of Veterinary and Life Sciences, Murdoch University, Perth, WA, Australia; 8Australian Animal Health Laboratory, East Geelong, VIC, Australia; 9College of Natural and Computational Sciences, Pacific University, Kaneohe, HI, USA
Cetacean morbillivirus (CeMV) is a member of the genus Morbillivirus in the family Paramyxoviridae that includes enveloped negative-sense RNA viruses of importance in both human and veterinary medicine. Over the past 25 years, CeMV has emerged as the most significant pathogen of dolphins. We describe the phylogenomic diversity among four CeMV strains: dolphin morbillivirus (DMV-M) isolated from a Mediterranean striped dolphin (Stenella coeruleoalba), dolphin morbillivirus (DMV-G) from a bottlenose dolphin (Tursiops truncatus) in the Gulf of Mexico, porpoise morbillivirus (PMV) isolated from a harbor porpoise (Phocoena phocoena), and beaked whale morbillivirus (BWMV) from Longman's beaked whale (Indopacetus pacificus). Full CeMV genomes were sequenced by performing overlapping reverse transcription PCR. The phylogenomic diversity of the CeMV strains were compared to the five other recognized morbillivirus species including: Measles virus, Rinderpest virus, Peste-des-petits-ruminants, Phocine distemper virus, Canine distemper virus, and Feline morbillivirus. Sequences were aligned in MAFFT 7.0 followed by evolutionary model optimization and Maximum Likelihood analysis in MEGA 6.0. The four CeMV strains formed a well-supported clade with 98% bootstrap support. BWMV was the most divergent and formed the sister taxon to the rest of the CeMVs. The DMVs and PMV formed a well-supported monophyletic group with 97% bootstrap support. Although considerable sequence variation was detected among the four, the magnitude of the difference was suggestive of separate CeMV strains rather than separate morbillivirus species. Although preliminary, recent detections of a highly divergent morbillivirus in Indo-Pacific bottlenose dolphins (T. aduncus) from Western Australia and a Guiana dolphin (Sotalia guianensis) from Brazil suggests the creation of a new morbillivirus species may be warranted. This study provides a much needed update to morbillivirus taxonomy, a foundation for future efforts aimed at developing improved CeMV molecular diagnostics, and a better understanding of the temporospatial dynamics of these emerging marine mammal pathogens.
The authors wish to thank Dr. Michael Walsh, Dr. Natalie Steckler, Jared Freitas, Dr. Jason Ferrante, Patrick Thompson and Abigail Clark of the University of Florida - College of Veterinary Medicine, Dr. John Lednicky of the University of Florida - College of Public Health and Health Professions, Blair Mase-Guthrie of National Marine Fisheries. This work was partially funded by the National Oceanic and Atmospheric Administration grant (NA14NMF46090276).
* Presenting author
+ Student presenter