First Report of Ranavirus Infecting Lungless Salamanders

Ranaviruses are a group of pathogens belonging to the genus Ranavirus (Family Iridoviridae) that have been linked to catastrophic die-offs of larval amphibians in North America and elsewhere (Daszak et al. 2003). They also have been identifi ed as the etiologic agent in the mass mortality of adult Common Frogs (Rana temporaria) and Common Toads (Bufo bufo) in the United Kingdom (Cunningham et al. 1996; 2007a,b). In the United States, ranaviruses are responsible for the majority of disease-related mortality events in amphibians (Green et al. 2002; Muths et al. 2006). There is evidence that ranaviruses may be an emerging infectious disease (Storfer et al. 2007), possibly due to novel strain introduction (Picco and Collins 2008) or increased occurrence of anthropogenic stressors on the landscape (Forson and Storfer 2006; Gray et al. 2007). Recognizing the potential threat of ranaviruses to global amphibian biodiversity, the World Organization for Animal Health (OIE) recently listed this pathogen as a notifi able disease, requiring proof of Ranavirus-negative results before commercial shipment of amphibians (OIE 2008). The OIE identifi es fi eld surveillance as a critical component of risk assessment for ranaviruses (OIE 2008). Although surveillance for the amphibian pathogen Batrachochytrium dendrobatidis has become widespread (e.g., Chatfi eld et al. 2009; Rothermel et al. 2008), testing amphibians for Ranavirus occurs less frequently. The Southern Appalachian Mountain Range of North America represents a global hotspot for salamander biodiversity (Dodd 2004; Petranka 1998). In particular, lungless salamanders (Family Plethodontidae) occur in high abundance and biomass (Peterman et al. 2008; Petranka and Murray 2001) and are important components of the ecosystem (Davic and Welsh 2004). Known die-offs of Eastern Newts (Notophthalmus viridescens), Spotted Salamanders (Ambystoma maculatum), Pickerel Frogs (Lithobates palustris), and Wood Frogs (L. sylvaticus) occurred in the Southern Appalachian Mountains due to ranaviruses in 1999 and 2001 (Converse and Green 2005; Green et al. 2002). Despite these mortality events, surveillance for Ranavirus in Southern Appalachian amphibians has been nonexistent. Our goal was to test for the presence of Ranavirus in lungless salamander communities located in the Southern Appalachian Mountains. We tested for Ranavirus in salamander communities at three sites that differed in elevation and report prevalence by species and for each site