Abstract
The marine iguana (Amblyrhynchus cristatus) is a vulnerable species composed of 10 recognized subpopulations endemic to the Galapagos Islands. El Niño events can cause up to 85% mortality. Other threats described include pollution and predation by invasive and domestic species.3 An unusual mortality event (UME) impacted multiple marine iguana colonies starting in early September 2013. Some animals presented with vomiting, and at necropsy, many animals had oral ulceration, stomatitis, and enteritis. Lesions were especially severe in the dorsal mucosa of the tongue and suggested a possible viral infection. We focused initially on viruses that have caused similar clinical presentations in other reptiles. We used previously established protocols for virus detection that have been proven in our laboratory. Consensus PCR protocols were used for detection of adenoviruses, herpesviruses, polyomaviruses, orthoreoviruses, and iridoviruses.1,2,4-6 Sixteen ethanol-stored samples from six animals have been tested. A novel herpesvirus has been identified in a low percentage of the samples analyzed. Phylogenetic analysis indicates that this is a new Alphaherpesvirus, here called Iguanid Herpesvirus-3 (IHV-3). IHV-3 is 77% similar to Iguanid Herpesvirus-2 (IHV-2) at the amino acid level. IHV-2 has been associated with hepatic necrosis in San Esteban chuckwallas (Sauromalus varius). IHV-3 and IHV-2 form a clade with 94% bootstrap support in the phylogenetic analysis.
Acknowledgments
The authors wish to thank the Galápagos National Park Directorate for supporting field work and samples exportation permits; Galápagos Conservancy, Lindblad/National Geographic, International Galápagos Tour Operators Association (IGTOA) for financial support; We also thank the collaboration of University of Florida, Northwest ZooPath, Houston Zoo, Inc., and the Charles Darwin Foundation.
Literature Cited
1. Fagrouch Z, Sarwari R, Lavergne A, Delaval M, De Thoisy B, Lacoste V, Verschoor EJ. Novel polyomaviruses in South American bats and their relationship to other members of the family Polyomaviridae. J Gen Virol. 2012;93:2652–2657.
2. Hanson LA, Rudis MR, Vasquez-Lee M, Montgomery RD. A broadly applicable method to characterize large DNA viruses and adenoviruses based on the DNA polymerase gene. Virol J. 2006;3:28.
3. Nelson K, Snell H, Wikelski M. Amblyrhynchus cristatus. In: IUCN 2013. IUCN Red List of Threatened Species. Version 2013.2. <www.iucnredlist.org>. Downloaded on 17 March 2014.
4. VanDevanter DR, Warrener P, Bennett L, Schultz ER, Coulter S, Garber RL, Rose TM. Detection and analysis of diverse herpesviral species by consensus primer PCR. J Clin Microbiol. 1996;34:1666–1671.
5. Wellehan J, Johnson A, Harrach B, Benko M, Pessier A, Johnson C, Garner M, Childress A, Jacobson E. Detection and analysis of six lizard adenoviruses by consensus primer PCR provides further evidence of a reptilian origin for the atadenoviruses. J Virol. 2004;78:13366–13369.
6. Wellehan Jr JF, Childress AL, Marschang RE, Johnson AJ, Lamirande EW, Roberts JF, Vickers ML, Gaskin JM, Jacobson ER. Consensus nested PCR amplification and sequencing of diverse reptilian, avian, and mammalian orthoreoviruses. Vet Microbiol. 2009;133:34–42.