WERC Publication Brief: Testudinid herpesvirus 2 detected in wild desert tortoises fo the first time. Updated July 2012.
THIS BRIEF REFERS TO:
Jacobson, ER, KH Berry, JFX Wllehan Jr, F Origgi, AL Childress, J Braun, M Schrenzel, J Yee, B Rideout. 2012. Serologic and molecular evidence for testudinid herpesvirus 2 infection in wild Agassiz’s desert tortoise, Gopherus agassizii. Journal of Wildlife Diseases 48(3): 747-757.
Much attention has been given to detecting emerging infectious diseases in Agassiz’s desert tortoise (Gopherus agassizii), a federally listed threatened species. Thousands of wild desert tortoises are being translocated as a result of military and industrial development. In addition, well-meaning citizens release unwanted captive tortoises, although such unauthorized releases are illegal. Infected translocated or released tortoises can spread pathogens through close contact during courtship, combat, and other intraspecific activities.
Herpesviruses are well-recognized pathogens of tortoises and turtles. Herpesvirus-like lesions were first reported in a captive tortoise in 1982, and wild tortoises with oral lesions suggestive of herpesvirus were described in 2003. Four types of herpesvirus genotypes have been recognized in turtles and tortoises to date: TeHV1, TeHV2, TeHV3 and TeHV4.
In a paper published in Journal of Wildlife Diseases in 2012, researchers from the University of Florida, USGS, University of Bern, and San Diego Zoo necropsied two wild adult male desert tortoises with gross lesions consistent with trauma and puncture wounds. One tortoise was from the central Mojave Desert of California and the other tortoise was from the northeastern Mojave Desert in southern Nevada. DNA samples from the tongue of the California tortoise and from the tongue and nasal mucosa of the Nevada tortoise showed 100% nucleotide identity with TeHV2. Researchers also reported antibody prevalence of 30.9% for a second herpesvirus, TeHV3, in surveys of 256 wild and 55 captive tortoises from the Mojave and Colorado deserts of California.
Although several cases of herpesvirus infection have been described in captive desert tortoises, these findings represent the first conclusive molecular evidence of TeHV2 infection in wild desert tortoises.