Two Novel Alpha Herpes Viruses Associated with Fatal Disseminated Infections in Bottlenose Dolphins (Tursiops truncatus)
Two immature female bottlenose dolphins (Tursiops truncatus) were found stranded on the U.S. Atlantic
coast. Necropsy and histopathologic examination of both dolphins demonstrated acute necrotizing lesions in multiple organ systems.
Commonly seen in these lesions were cells with enlarged nuclei that contained single 4-6µm diameter homogeneous eosinophilic
inclusion bodies which were often surrounded by a clear halo. Ultrastructural examination revealed that intranuclear inclusions
contained 90-110 nm-diameter viral particles with electron-dense cores and hexagonal profiles. Rarely, viral particles were present in
the cytoplasm and were surrounded by variably electron-dense envelopes; enveloped virions were 140 nm in diameter. Polymerase chain
reactions targeting the DNA polymerase and terminase genes of herpesviruses were carried out on unfixed tissues of both animals, and
analysis of the DNA products indicated the presence of two novel alpha herpesviruses. The gross, histologic, ultrastructural, and
molecular genetic findings indicate disseminated herpes viral infections; the lack of evidence of any other primary pathogenic
organisms supports the conclusion that the alpha herpesviruses caused the deaths of the two dolphins. This is the first report of
disseminated herpes viral infection in cetaceans.
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