Two novel alphaherpesviruses associated with fatal disseminated infectionsin Atlantic bottlenose dolphins

Two immature female bottlenose dolphins (Tursiops truncatus) were found str anded on the Atlantic coast of the USA. Necropsy and histopathologic examin ation of both dolphins demonstrated acute necrotizing lesions in multiple o rgan systems. Commonly seen in these lesions were cells with enlarged nucle i that contained single 4 to 6 mum diameter homogeneous eosinophilic inclus ion bodies that were often surrounded by a clear halo. Ultrastructural exam ination revealed that intranuclear inclusions contained 90 to 110 nm diamet er viral particles with electron-dense cores and hexagonal profiles. Viral particles were also present in the cytoplasm, and these were surrounded by variable electron-dense envelopes. Enveloped virions were 140 nm in diamete r. Polymerase chain reactions targeting the DNA polymerase and terminase ge nes of herpesviruses were carried out on unfixed tissues of both animals, a nd analysis of the DNA products indicated the presence of two novel alphahe rpesviruses. The gross, histologic, ultrastructural, and molecular genetic findings indicate disseminated herpesviral infections, and support the conc lusion that tile alphaherpesviruses caused the deaths of the two dolphins. This is the first report of disseminated herpesviral infection in cetaceans .