Snake fungal disease is an infectious disease confirmed in numerous species of snakes caused by the fungus Ophidiomyces ophidiicola.
Historically, reports of snakes with skin infections of unknown origin have been sporadic. Recently, the number of reported cases of skin infections in snakes has increased substantially. As of August 2017, the fungus Ophidiomyces ophidiicola has been detected in much of the eastern half of the U.S. However, researchers suspect that snake fungal disease (SFD) may be more widely distributed than these documented cases suggest, because efforts to monitor the health of many snake populations are limited. Snake fungal disease may also be underreported in populations where it affects snakes infrequently or in species that develop less severe illness.
Signs of SFD include localized thickening or crusting of the skin, ulcerated skin, nodules (that is, abnormal bumps) under the skin, abnormal molting, white opaque cloudiness of the eyes (not associated with molting), and facial disfiguration that can be quite severe, leading to emaciation and death. Many snake populations are already in decline and the recent emergence of SFD may accelerate this decline, causing certain species to disappear entirely from some locations.
In 2016 scientists from the National Wildlife Health Center (NWHC) published a study demonstrating that SFD is widespread in eastern North America, has a broad host range among snakes, and is the predominant cause of skin infections in wild snakes. The study also showed that O. ophiodiicola frequently causes non-lethal infections in snakes and that environmental changes are likely causing the recent emergence of severe and fatal infections in some snake populations. The NWHC has continued to participate in collaborative projects with multiple state natural resource agencies aimed at better understanding SFD and its potential impacts on snake populations. In support of this effort, the NWHC has analyzed samples from over 100 whole carcasses and biopsies from snakes exhibiting clinical signs consistent with SFD. The NWHC is working with researchers to better understand the epidemiology of SFD in different snake populations in North America and abroad. The intent of this research is to determine the spatial extent and severity of this disease in wild populations to determine if intervention is needed to reduce its impacts on sensitive populations.
We encourage conservation agencies and natural resource managers to contact the NWHC if snakes with clinical signs consistent with SFD are encountered.
For more information on snake fungal disease, see the USGS Fact Sheet: Snake fungal disease in North America: U.S. Geological Survey updates.
Below are publications about snake fungal disease.
Snake fungal disease in North America: U.S. Geological Survey updates
Field diagnostics and seasonality of Ophidiomyces ophiodiicola in wild snake populations
Seasonal sex steroids indicate reproductive costs associated with snake fungal disease
Patterns of circulating corticosterone in a population of rattlesnakes afflicted with snake fungal disease: Stress hormones as a potential mediator of seasonal cycles in disease severity and outcomes
Host susceptibility to snake fungal disease is highly dispersed across phylogenetic and functional trait space
Snake fungal disease in North America: U.S. Geological Survey updates
Emerging fungal pathogen Ophidiomyces ophiodiicola in wild European snakes
Snake fungal disease: An emerging threat to wild snakes
Experimental infection of snakes with Ophidiomyces ophiodiicola causes pathological changes that typify snake fungal disease
Detection of snake fungal disease due to Ophidiomyces ophiodiicola in Virginia, USA
TaqMan real-time polymerase chain reaction for detection of Ophidiomyces ophiodiicola, the fungus associated with snake fungal disease
Below are news stories about snake fungal disease.
- Overview
Snake fungal disease is an infectious disease confirmed in numerous species of snakes caused by the fungus Ophidiomyces ophidiicola.
Historically, reports of snakes with skin infections of unknown origin have been sporadic. Recently, the number of reported cases of skin infections in snakes has increased substantially. As of August 2017, the fungus Ophidiomyces ophidiicola has been detected in much of the eastern half of the U.S. However, researchers suspect that snake fungal disease (SFD) may be more widely distributed than these documented cases suggest, because efforts to monitor the health of many snake populations are limited. Snake fungal disease may also be underreported in populations where it affects snakes infrequently or in species that develop less severe illness.
Signs of SFD include localized thickening or crusting of the skin, ulcerated skin, nodules (that is, abnormal bumps) under the skin, abnormal molting, white opaque cloudiness of the eyes (not associated with molting), and facial disfiguration that can be quite severe, leading to emaciation and death. Many snake populations are already in decline and the recent emergence of SFD may accelerate this decline, causing certain species to disappear entirely from some locations.
In 2016 scientists from the National Wildlife Health Center (NWHC) published a study demonstrating that SFD is widespread in eastern North America, has a broad host range among snakes, and is the predominant cause of skin infections in wild snakes. The study also showed that O. ophiodiicola frequently causes non-lethal infections in snakes and that environmental changes are likely causing the recent emergence of severe and fatal infections in some snake populations. The NWHC has continued to participate in collaborative projects with multiple state natural resource agencies aimed at better understanding SFD and its potential impacts on snake populations. In support of this effort, the NWHC has analyzed samples from over 100 whole carcasses and biopsies from snakes exhibiting clinical signs consistent with SFD. The NWHC is working with researchers to better understand the epidemiology of SFD in different snake populations in North America and abroad. The intent of this research is to determine the spatial extent and severity of this disease in wild populations to determine if intervention is needed to reduce its impacts on sensitive populations.
We encourage conservation agencies and natural resource managers to contact the NWHC if snakes with clinical signs consistent with SFD are encountered.
For more information on snake fungal disease, see the USGS Fact Sheet: Snake fungal disease in North America: U.S. Geological Survey updates.
- Multimedia
- Publications
Below are publications about snake fungal disease.
Snake fungal disease in North America: U.S. Geological Survey updates
Snake fungal disease (SFD) results from a skin infection that has been documented only in snakes. Historically, reports of snakes with skin infections of unknown origin have been sporadic. Recently, the number of reported cases of skin infections in snakes has increased substantially. This emerging infectious disease, confirmed in numerous species of snakes, is caused by the fungus Ophidiomyces opAuthorsNoelle E. Thompson, Emily W. Lankau, Gail Moede RogallField diagnostics and seasonality of Ophidiomyces ophiodiicola in wild snake populations
Snake fungal disease (SFD) is an emerging disease caused by the fungal pathogen, Ophidiomyces ophiodiicola. Clinical signs of SFD include dermal lesions, including regional and local edema, crusts, and ulcers. Snake fungal disease is widespread in the Eastern United States, yet there are limited data on how clinical signs of SFD compare with laboratory diagnostics. We compared two sampling methodsAuthorsJennifer M. McKenzie, Steven J. Price, J. Leo Fleckenstein, Andrea N. Drayer, Grant M. Connette, Elizabeth A. Bohuski, Jeffrey M. LorchSeasonal sex steroids indicate reproductive costs associated with snake fungal disease
Emergent diseases may result in population declines by inducing mortality directly or through sublethal effects on host reproduction. Snake fungal disease (SFD) is an emerging threat to biodiversity, but the sublethal impacts of disease on host fitness are poorly characterized in snakes. The cryptic nature of most snakes makes direct assessment of the fitness consequences of SFD challenging. In suAuthorsCraig M. Lind, Jeffrey M. Lorch, Ignacio T. Moore, Ben J. Vernasco, Terence M. FarrellPatterns of circulating corticosterone in a population of rattlesnakes afflicted with snake fungal disease: Stress hormones as a potential mediator of seasonal cycles in disease severity and outcomes
Snake fungal disease (SFD) is an emerging threat to snake populations in the United States. Fungal pathogens are often associated with a physiological stress response mediated by the hypothalamo-pituitary-adrenal axis (HPA), and afflicted individuals may incur steep coping costs. The severity of SFD can vary seasonally; however, little is known regarding (1) how SFD infection relates to HPA activiAuthorsCraig M. Lind, Ignacio T. Moore, Çağlar Akçay, Ben J. Vernasco, Jeffrey M. Lorch, Terence M. FarrellHost susceptibility to snake fungal disease is highly dispersed across phylogenetic and functional trait space
Emerging infectious diseases (EIDs) reduce host population sizes, cause extinction, disassemble communities, and have indirect negative effects on human well-being. Fungal EIDs have reduced population abundances in amphibians and bats across many species over large areas. The recent emergence of snake fungal disease (SFD) may have caused declines in some snake populations in the Eastern United StaAuthorsFrank T. Burbrink, Jeffrey M. Lorch, Karen R. LipsSnake fungal disease in North America: U.S. Geological Survey updates
Snake fungal disease (SFD) results from a skin infection that has been documented only in snakes. Historically, reports of snakes with skin infections of unknown origin have been sporadic. Recently, the number of reported cases of skin infections in snakes has increased substantially. This emerging infectious disease, confirmed in numerous species of snakes, is caused by the fungus Ophidiomyces opAuthorsNoelle E. Thompson, Emily W. Lankau, Gail Moede RogallEmerging fungal pathogen Ophidiomyces ophiodiicola in wild European snakes
Snake fungal disease (SFD) is an emerging disease of conservation concern in eastern North America. Ophidiomyces ophiodiicola, the causative agent of SFD, has been isolated from over 30 species of wild snakes from six families in North America. Whilst O. ophiodiicola has been isolated from captive snakes outside North America, the pathogen has not been reported from wild snakes elsewhere. We screeAuthorsLydia H. V. Franklinos, Jeffrey M. Lorch, Elizabeth A. Bohuski, Julia Rodriguez-Ramos Fernandez, Owen Wright, Liam Fitzpatrick, Silviu Petrovan, Chris Durrant, Chris Linton, Vojtech Baláž, Andrew A Cunningham, Becki LawsonSnake fungal disease: An emerging threat to wild snakes
Since 2006, there has been a marked increase in the number of reports of severe and often fatal fungal skin infections in wild snakes in the eastern USA. The emerging condition, referred to as snake fungal disease (SFD), was initially documented in rattlesnakes, where the infections were believed to pose a risk to the viability of affected populations. The disease is caused byOphidiomyces ophiodiiAuthorsJeffrey M. Lorch, Susan Knowles, Julia S. Lankton, Kathy Michell, Jaime L. Edwards, Joshua M. Kapfer, Richard A. Staffen, Erik R. Wild, Katie Z. Schmidt, Anne Ballmann, Doug Blodgett, Terence M. Farrell, Brad M. Glorioso, Lisa A. Last, Steven J. Price, Krysten L. Schuler, Christopher Smith, James F. X. Wellehan, David S. BlehertExperimental infection of snakes with Ophidiomyces ophiodiicola causes pathological changes that typify snake fungal disease
Snake fungal disease (SFD) is an emerging skin infection of wild snakes in eastern North America. The fungus Ophidiomyces ophiodiicola is frequently associated with the skin lesions that are characteristic of SFD, but a causal relationship between the fungus and the disease has not been established. We experimentally infected captive-bred corn snakes (Pantherophis guttatus) in the laboratory withAuthorsJeffrey M. Lorch, Julia S. Lankton, Katrien Werner, Elizabeth A. Falendysz, Kevin McCurley, David S. BlehertDetection of snake fungal disease due to Ophidiomyces ophiodiicola in Virginia, USA
Snake fungal disease (SFD) is an emerging disease of wildlife believed to be caused by Ophidiomyces ophiodiicola. Although geographic and host ranges have yet to be determined, this disease is characterized by crusty scales, superficial pustules, and subcutaneous nodules, with subsequent morbidity and mortality in some snake species. To confirm the presence of SFD and O. ophiodiicola in snakes ofAuthorsAmanda L. Guthrie, Susan Knowles, Anne Ballmann, Jeffrey M. LorchTaqMan real-time polymerase chain reaction for detection of Ophidiomyces ophiodiicola, the fungus associated with snake fungal disease
Background Fungal skin infections associated with Ophidiomyces ophiodiicola, a member of the Chrysosporiumanamorph of Nannizziopsis vriesii (CANV) complex, have been linked to an increasing number of cases of snake fungal disease (SFD) in captive snakes around the world and in wild snake populations in eastern North America. The emergence of SFD in both captive and wild situations has led to an iAuthorsElizabeth A. Bohuski, Jeffrey M. Lorch, Kathryn M. Griffin, David S. Blehert - News
Below are news stories about snake fungal disease.