BRIEF REPORT Morbillivirus infection in pilot whales: strict protein requirement drives genetic conservation Ashley C. Banyard • Ashok Tiwari • Thomas Barrett Received: 14 March 2011 / Accepted: 26 May 2011 / Published online: 14 June 2011 Ó Springer-Verlag 2011 Abstract Morbillivirus infection of marine mammals has been documented across all of the world’s oceans. Whilst infection is generally demonstrated using a variety of his- topathological and serological techniques, where possible, the use of molecular techniques is being used to enable accurate genetic typing of virus strains through sequence analysis. Here, we present genetic data from dolphins and pilot whales affected by morbillivirus infection in the recent outbreak in the Mediterranean Sea during a six- month period from the end of October 2006 to April 2007. To date, very few studies have looked at characterizing outbreaks of morbillivirus infections in whale species at the molecular level. Here, we provide a full sequence for the haemagglutinin (H) gene from material derived from both a dolphin and a pilot whale from the 2007 outbreak in the Mediterranean Sea and show this virus to be 100% iden- tical across the region analysed. Furthermore, we compare partial sequence data from the nucleocapsid (N) gene of the pilot whale material with previously published data and show evidence for strong protein conservation between these different isolates. Finally, we discuss the current classification of cetacean morbilliviruses as a single species. Keywords Morbillivirus Á Cetacean Á Whale Cetacean infection with morbilliviruses is believed to be widespread. To date, two main morbilliviruses of marine mammals have been characterized at the molecular level and named according to the species in which they were discovered: porpoise morbillivirus (PMV) and dolphin morbillivirus (DMV). PMV was originally isolated from European harbour porpoises (Phocoena phocoena) that washed up along the coastline of Ireland in 1988 [17]. Whilst PMV outbreaks have been relatively few, outbreaks of DMV infection have been more frequent, with infections occurring epizootically in common dolphins (Delphinus delphis ponticus) [21], Atlantic bottlenose dolphins (Tursiops truncates)[23], striped dolphins (Stenella co- eruleoalba)[9, 10, 27, 28], and Risso’s dolphins (Grampus griseus)[29]. An epidemic of DMV in Stenella coeruleo- alba was documented along the Spanish coast between October 2006 and April 2007 involving the deaths of hundreds of dolphins [20]. During this outbreak, a number long-finned pilot whales were also washed up along the southern Spanish Mediterranean coast and Balearic Islands and found to be positive for morbillivirus antigen [12]. Circulation of morbilliviruses within cetacean populations remains an enigma. However, when possible, the genetic typing of viruses has enabled comparisons to be made between viruses that have caused disease in different spe- cies. Sequence generated from a pilot whale that stranded on the coast of New Jersey, USA, in 2000 suggested that T. Barrett: deceased on 19 September 2009. A. C. Banyard Á T. Barrett Institute for Animal Health, Pirbright Laboratory, Ash Road, Woking, Surrey GU24 0NF, UK A. Tiwari Molecular Biology Laboratory, Division of Animal Biotechnology, Indian Veterinary Research Institute, Izatnagar 243 122, UP, India Present Address: A. C. Banyard (&) Wildlife Zoonoses and Vector Borne Disease Research Group, Animal Health and Veterinary Laboratories Agency, Weybridge, Surrey KT15 3NB, UK e-mail: ashley.banyard@ahvla.gsi.gov.uk 123 Arch Virol (2011) 156:1853–1859 DOI 10.1007/s00705-011-1042-8