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 images related to snake fungal disease.
Below are publications about snake fungal disease.
Snake fungal disease in North America: U.S. Geological Survey updates
Prevalence of Ophidiomyces ophidiicola and epizootiology of snake fungal disease in free-ranging Northern Pine Snakes (Pituophis melanoleucus melanoleucus) in New Jersey
A cross inoculation experiment reveals Ophidiomyces ophiodiicola and Nannizziopsis guarroi can each infect both snakes and lizards
Ophidiomycosis is related to seasonal patterns of reproduction, ecdysis, and thermoregulatory behavior in a free-living snake species
The population genetics of the causative agent of snake fungal disease indicate recent introductions to the USA
Soil reservoir dynamics of ophidiomyces ophidiicola, the causative agent of snake fungal disease
Effects of snake fungal disease on short‐term survival, behavior, and movement in free‐ranging snakes
Evidence of vertical transmission of the snake fungal pathogen Ophidiomyces ophiodiicola
Interactive effects of food supplementation and snake fungal disease on pregnant Pygmy Rattlesnakes and their offspring
Field diagnostics and seasonality of Ophidiomyces ophiodiicola in wild snake populations
Seasonal sex steroids indicate reproductive costs associated with snake fungal disease
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
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
Below are images related to snake fungal disease.
- 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 RogallFilter Total Items: 19Prevalence of Ophidiomyces ophidiicola and epizootiology of snake fungal disease in free-ranging Northern Pine Snakes (Pituophis melanoleucus melanoleucus) in New Jersey
Snake fungal disease, caused by Ophidiomyces ophidiicola, is recognized as a potential concern for North American snakes. We tested skin swabs from Northern Pine Snakes (Pituophis melanoleucus melanoleucus) in the New Jersey pinelands for the presence of O. ophidiicola before emergence from hibernation. We used qPCR to test the collected swabs for the presence of O. ophidiicola, then determined paAuthorsJoanna Burger, Michael Gochfeld, Robert T. Zappalorti, John F. Bunnell, Christian Jeitner, David Schneider, Kelly Ng, Emile DeVito, Jeffrey M. LorchA cross inoculation experiment reveals Ophidiomyces ophiodiicola and Nannizziopsis guarroi can each infect both snakes and lizards
Host range and specificity are key concepts in the study of infectious diseases. However, both concepts remain largely undefined for many influential pathogens, including many fungi within the Onygenales order. This order encompasses reptile-infecting genera (Nannizziopsis, Ophidiomyces, and Paranannizziopsis) formerly classified as the Chrysosporium anamorph of Nannizziopsis vriesii (CANV). The rAuthorsSavannah L Gentry, Jeffrey M. Lorch, Julia S. Lankton, Anne PringleOphidiomycosis is related to seasonal patterns of reproduction, ecdysis, and thermoregulatory behavior in a free-living snake species
Informed and effective management of emerging infectious diseases can be improved by a clear understanding of host–pathogen–environment interactions. Impacts of the seasonal environment on pathogen dynamics and host responses are poorly described in most reptile host–fungal pathogen systems. Here, we describe seasonal patterns of ophidiomycosis, a disease caused by the fungus Ophidiomyces ophidiicAuthorsC. M. Lind, J. Agugliaro, Jeffrey M. Lorch, T. M. FarrellThe population genetics of the causative agent of snake fungal disease indicate recent introductions to the USA
Snake fungal disease (SFD; ophidiomycosis), caused by the pathogen Ophidiomyces ophiodiicola (Oo), has been documented in wild snakes in North America and Eurasia, and is considered an emerging disease in the eastern United States of America. However, a lack of historical disease data has made it challenging to determine whether Oo is a recent arrival to the USA or whether SFD emergence is due toAuthorsJason T. Ladner, Jonathan M. Palmer, Cassandra L. Ettinger, Jason E. Stajich, Terence M. Farrell, Brad M. Glorioso, Becki Lawson, Steven J. Price, Anne G. Stengle, Daniel A. Grear, Jeffrey M. LorchSoil reservoir dynamics of ophidiomyces ophidiicola, the causative agent of snake fungal disease
Wildlife diseases pose an ever-growing threat to global biodiversity. Understanding how wildlife pathogens are distributed in the environment and the ability of pathogens to form environmental reservoirs is critical to understanding and predicting disease dynamics within host populations. Snake fungal disease (SFD) is an emerging conservation threat to North American snake populations. The causatiAuthorsLewis J. Campbell, Joanna Burger, Robert T. Zappalorti, John F. Bunnell, Megan Winzeler, Daniel R. Taylor, Jeffrey M. LorchEffects of snake fungal disease on short‐term survival, behavior, and movement in free‐ranging snakes
Pathogenic fungi are increasingly associated with epidemics in wildlife populations. Snake fungal disease (SFD, also referred to as Ophidiomycosis) is an emerging threat to snakes, taxa that are elusive and difficult to sample. Thus, assessments of the effects of SFD on populations have rarely occurred. We used a field technique to enhance detection, Passive Integrated Transponder (PIT) telemetry,AuthorsJennifer M. McKenzie, Steven J. Price, Grant M. Connette, Simon J Bonner, Jeffrey M. LorchEvidence of vertical transmission of the snake fungal pathogen Ophidiomyces ophiodiicola
Snake fungal disease (ophidiomycosis) is an emerging infection of snakes caused by Ophidiomyces ophiodiicola. Little is known about mechanisms of this pathogen's transmission and its implications for conservation of wild snake populations. We report four cases with evidence of vertical transmission of O. ophiodiicola from dam to offspring.AuthorsAnne G Stengle, Terence M. Farrell, Keenan S Freitas, Craig M. Lind, Steven J. Price, Brian O Butler, Tigran Tadevosyan, Marcos Isidoro Ayza, Daniel Taylor, Megan Winzeler, Jeffrey M. LorchInteractive effects of food supplementation and snake fungal disease on pregnant Pygmy Rattlesnakes and their offspring
In viviparous organisms, the ability to feed while pregnant may mitigate energetic trade-offs experienced during the reproductive process and enhance fecundity. However, anorexia during pregnancy has been reported in many crotaline snakes. The potential costs and benefits of feeding while pregnant are not completely described in the literature, and experimental studies have been conducted in a limAuthorsCraig M. Lind, Amber Clark, Sarah A Smiley-Walters, Daniel Taylor, Marcos Isidoro Ayza, Jeffrey M. Lorch, Terence M. FarrellField 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. FarrellSeasonal 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. Farrell - News
Below are news stories about snake fungal disease.