Nested PCR Amplification and Sequencing of Diverse Reptile Reoviruses
American Association of Zoo Veterinarians Conference 2006
James F.X. Wellehan1, DVM, MS, DACZM; April J. Johnson1, DVM; Rachel E. Marschang3, DrMedVet; John F. Roberts2, DVM; Mary Lynne Vickers4, PhD; April Childress1; Elliott R. Jacobson1, MS, DVM, PhD, DACZM
1Zoological Medicine Service, Department of Small Animal Clinical Sciences, and 2Department of Veterinary Pathology, College of Veterinary Medicine, University of Florida, Gainesville, FL, USA; 3Institut für Umwelt- und Tierhygiene, Hohenheim University, Stuttgart, Germany; 4Livestock Disease Diagnostic Center, University of Kentucky, Lexington, KY, USA
Reoviruses have been shown to cause fatal pneumonia and subacute tracheitis in reptiles.1 Diagnosis is challenging, as there are no inclusions, and histologic lesions resemble paramyxoviral disease. Serologic diagnosis has been limited to virus neutralization, which is labor intensive and may not cross-react between strains.2 As reptile reoviruses do not hemagglutinate, hemagglutination inhibition is not an option. RNA-dependent RNA polymerase sequences from mammalian orthoreoviruses and piscine aquareoviruses were aligned. Degenerate primers were designed targeting conserved regions. These primers were used in a nested PCR to amplify sequences from 11 reovirus isolates from snake and chelonian species. Nucleotide sequencing of the PCR products showed that the reoviral sequences from these reptiles were novel and represented seven distinct strains. Comparative sequence analysis shows that these viruses are probable members of the genus Orthoreovirus. These primers may be of use for obtaining initial sequence data from novel reoviruses. Further understanding and identification of reoviral types and species will provide useful diagnostic, prognostic, and epidemiologic information for the clinician.
1. Lamirande, E.W., D.K. Nichols, J.W. Owens, J.M. Gaskin, and E.R. Jacobson. 1999. Isolation and experimental transmission of a reovirus pathogenic in ratsnakes (Elaphe species). Virus Res. 63:135–141.
2. Marschang, R.E., S. Donahoe, R. Manvell, and J. Lemos-Espinal. 2002. Paramyxovirus and reovirus infections in wild-caught Mexican lizards (Xenosaurus and Abronia spp.). J. Zoo Wildl. Med. 33:317–321.