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What is chronic wasting disease?

Chronic wasting disease (CWD) is a fatal, neurological illness occurring in North American cervids (members of the deer family), including white-tailed deer, mule deer, elk, and moose. Since its discovery in 1967, CWD has spread geographically and increased in prevalence locally. CWD is contagious; it can be transmitted freely within and among cervid populations. No treatments or vaccines are currently available.

Chronic wasting disease is of great concern to wildlife managers. It has been detected in at least 23 states, two Canadian provinces, and South Korea. CWD is not known to infect livestock or humans.

CWD is transmitted directly through animal-to-animal contact, and indirectly through contact with objects or environment contaminated with infectious material (including saliva, urine, feces, and carcasses of CWD-infected animals).

Learn more:

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Photo of a bull elk with chronic wasting disease.

What are the visual signs of chronic wasting disease?

Chronic wasting disease (CWD) has an extended incubation period averaging 18–24 months between infection and the onset of noticeable signs. During this time frame animals look and act normal. The most obvious sign of CWD is progressive weight loss. Numerous behavioral changes also have been reported, including decreased social interaction, loss of awareness, and loss of fear of humans. Diseased...

link

What are the visual signs of chronic wasting disease?

Chronic wasting disease (CWD) has an extended incubation period averaging 18–24 months between infection and the onset of noticeable signs. During this time frame animals look and act normal. The most obvious sign of CWD is progressive weight loss. Numerous behavioral changes also have been reported, including decreased social interaction, loss of awareness, and loss of fear of humans. Diseased...

Learn More
link
Image shows a mule deer doe walking on grass, facing right

What causes chronic wasting disease?

Chronic wasting disease is caused by a misfolded protein called a prion. All mammals produce normal prions that are used by cells, then degraded and eliminated, or recycled, within the body. When disease-associated prions contact normal prions, they cause them to refold into their own abnormal shape. These disease-associated prions are not readily broken down and tend to accumulate in--and damage-...

link

What causes chronic wasting disease?

Chronic wasting disease is caused by a misfolded protein called a prion. All mammals produce normal prions that are used by cells, then degraded and eliminated, or recycled, within the body. When disease-associated prions contact normal prions, they cause them to refold into their own abnormal shape. These disease-associated prions are not readily broken down and tend to accumulate in--and damage-...

Learn More
Map of North America showing locations where chronic wasting disease has been detected.
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Ecosystems Podcast Series Episode 3 artwork
link
Photo of a bull elk with chronic wasting disease.
link
USGS CoreCast
link
Deer with Chronic Wasting Disease
link

Ungulate migrations of the western United States, volume 3

Ungulates (hooved mammals) have a broad distribution across the western United States and play an important role in maintaining predator-prey dynamics, affecting vegetation communities, and providing economic benefits to regional communities through tourism and hunting. Throughout the diverse landscapes they occupy, many ungulate populations undertake seasonal migrations to exploit spatially and t
By
Cooperative Research Units

Chronic wasting disease—Research by the U.S. Geological Survey and partners

IntroductionChronic wasting disease (CWD) is the only transmissible spongiform encephalopathy, a class of invariably fatal neurodegenerative mammalian diseases associated with a misfolded cellular prion protein found in wild free-ranging animals. Because it has a long incubation period, affected animals in Cervidae (the deer family; referred to as “cervids”) may not show signs of disease for sever
By
Ecosystems, Cooperative Research Units, Fish & Wildlife Disease, National Wildlife Health Center, Northern Rocky Mountain Science Center, Office of Science Quality and Integrity

U.S. Geological Survey response to chronic wasting disease

The U.S. Geological Survey (USGS) is focused on the development of early detection and effective response tools that promote an adaptive management approach to chronic wasting disease (CWD). USGS scientists across the United States are working to understand the biology of CWD, assess and predict the spread and persistence in wildlife and the environment, and develop tools for early detection and c
By
Ecosystems, Biological Threats and Invasive Species Research Program

Chronic wasting disease—Status, science, and management support by the U.S. Geological Survey

The U.S. Geological Survey (USGS) investigates chronic wasting disease (CWD) at multiple science centers and cooperative research units across the Nation and supports the management of CWD through science-based strategies. CWD research conducted by USGS scientists has three strategies: (1) to understand the biology, ecology, and causes and distribution of CWD; (2) to assess and predict the spread
By
Ecosystems, Biological Threats and Invasive Species Research Program, National Wildlife Health Center

Field Manual of Wildlife Diseases

Welcome to a new version of the “Field Manual of Wildlife Diseases.” Unlike the previous printed versions of this publication, this new version is being developed as a “living“ electronic publication. Content will periodically be added and (or) updated as warranted, and it will always be reviewed by scientific experts (“peer reviewed”) before it is released. Thus, this publication will never be co
By
Water Resources, Ecosystems, National Wildlife Health Center

Why bother about wildlife disease?

In most developed countries, the maintenance of the numbers of wildlife1 is vested in the natural resource agencies of those countries. During earlier times, game species were the primary focus of natural resource agencies2,3 however, current wildlife conservation continues to transition towards a more holistic focus on biodiversity4 and environmental health5,6. Nevertheless, that transition lags
By
Ecosystems, National Wildlife Health Center

Enhanced surveillance strategies for detecting and monitoring chronic wasting disease in free-ranging cervids

The purpose of this document is to provide wildlife management agencies with the foundation upon which they can build scientifically rigorous and cost-effective surveillance and monitoring programs for chronic wasting disease (CWD) or refine their existing programs. The first chapter provides an overview of potential demographic and spatial risk factors of susceptible wildlife populations that may
By
Ecosystems, National Wildlife Health Center

Chronic Wasting Disease

Chronic wasting disease (CWD) is an always-fatal, neurological illness occurring in North American cervids (members of the deer family), including white-tailed deer, mule deer, elk and moose. Since its discovery in 1967, CWD has spread geographically and increased in prevalence locally. CWD is contagious; it can be transmitted freely within and among free-ranging populations. It is likely that dis
By
Ecosystems, National Wildlife Health Center

Chronic Wasting Disease Positive Tissue Bank

In 2005, the USGS National Wildlife Health Center entered into an agreement with the Wyoming Game and Fish Department and the Department of Veterinary Sciences at the University of Wyoming to produce a collection of positive tissues from cervids intentionally infected with chronic wasting disease. This agreement was facilitated through the University of Wyoming Cooperative Fish and Wildlife Unit.
By
Ecosystems, National Wildlife Health Center

Disease emergence and resurgence—the wildlife-human connection

In 2000, the Global Outbreak Alert and Response Network (GOARN) was organized as a global disease watchdog group to coordinate disease outbreak information and health crisis response. The World Health Organization (WHO) is the headquarters for this network. Understandably, the primary focus for WHO is human health. However, diseases such as the H5N1 avian influenza epizootic in Asian bird populati
By
Ecosystems, National Wildlife Health Center
link

Chronic Wasting Disease: Can Science Save Our Dear Deer?

Chronic wasting disease is as ominous as it sounds for North American cervids.

Read Article
link

New Approach May Detect Chronic Wasting Disease Earlier, at Less Cost

A new statistical approach to disease surveillance may improve scientists’ and managers’ ability to detect chronic wasting disease earlier in white...

Read Article
link

Chronic Wasting Disease in White-Tailed Deer

Chronic wasting disease may have long-term negative effects on white-tailed deer, a highly visible and economically valuable keystone species...

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Related Content

  • FAQ
    link
    Photo of a bull elk with chronic wasting disease.

    What are the visual signs of chronic wasting disease?

    Chronic wasting disease (CWD) has an extended incubation period averaging 18–24 months between infection and the onset of noticeable signs. During this time frame animals look and act normal. The most obvious sign of CWD is progressive weight loss. Numerous behavioral changes also have been reported, including decreased social interaction, loss of awareness, and loss of fear of humans. Diseased...

    link

    What are the visual signs of chronic wasting disease?

    Chronic wasting disease (CWD) has an extended incubation period averaging 18–24 months between infection and the onset of noticeable signs. During this time frame animals look and act normal. The most obvious sign of CWD is progressive weight loss. Numerous behavioral changes also have been reported, including decreased social interaction, loss of awareness, and loss of fear of humans. Diseased...

    Learn More
    link
    Image shows a mule deer doe walking on grass, facing right

    What causes chronic wasting disease?

    Chronic wasting disease is caused by a misfolded protein called a prion. All mammals produce normal prions that are used by cells, then degraded and eliminated, or recycled, within the body. When disease-associated prions contact normal prions, they cause them to refold into their own abnormal shape. These disease-associated prions are not readily broken down and tend to accumulate in--and damage-...

    link

    What causes chronic wasting disease?

    Chronic wasting disease is caused by a misfolded protein called a prion. All mammals produce normal prions that are used by cells, then degraded and eliminated, or recycled, within the body. When disease-associated prions contact normal prions, they cause them to refold into their own abnormal shape. These disease-associated prions are not readily broken down and tend to accumulate in--and damage-...

    Learn More
  • Multimedia
    Map of North America showing locations where chronic wasting disease has been detected.
    link
    Ecosystems Podcast Series Episode 3 artwork
    link
    Photo of a bull elk with chronic wasting disease.
    link
    USGS CoreCast
    link
    Deer with Chronic Wasting Disease
    link
  • Publications

    Ungulate migrations of the western United States, volume 3

    Ungulates (hooved mammals) have a broad distribution across the western United States and play an important role in maintaining predator-prey dynamics, affecting vegetation communities, and providing economic benefits to regional communities through tourism and hunting. Throughout the diverse landscapes they occupy, many ungulate populations undertake seasonal migrations to exploit spatially and t
    By
    Cooperative Research Units

    Chronic wasting disease—Research by the U.S. Geological Survey and partners

    IntroductionChronic wasting disease (CWD) is the only transmissible spongiform encephalopathy, a class of invariably fatal neurodegenerative mammalian diseases associated with a misfolded cellular prion protein found in wild free-ranging animals. Because it has a long incubation period, affected animals in Cervidae (the deer family; referred to as “cervids”) may not show signs of disease for sever
    By
    Ecosystems, Cooperative Research Units, Fish & Wildlife Disease, National Wildlife Health Center, Northern Rocky Mountain Science Center, Office of Science Quality and Integrity

    U.S. Geological Survey response to chronic wasting disease

    The U.S. Geological Survey (USGS) is focused on the development of early detection and effective response tools that promote an adaptive management approach to chronic wasting disease (CWD). USGS scientists across the United States are working to understand the biology of CWD, assess and predict the spread and persistence in wildlife and the environment, and develop tools for early detection and c
    By
    Ecosystems, Biological Threats and Invasive Species Research Program

    Chronic wasting disease—Status, science, and management support by the U.S. Geological Survey

    The U.S. Geological Survey (USGS) investigates chronic wasting disease (CWD) at multiple science centers and cooperative research units across the Nation and supports the management of CWD through science-based strategies. CWD research conducted by USGS scientists has three strategies: (1) to understand the biology, ecology, and causes and distribution of CWD; (2) to assess and predict the spread
    By
    Ecosystems, Biological Threats and Invasive Species Research Program, National Wildlife Health Center

    Field Manual of Wildlife Diseases

    Welcome to a new version of the “Field Manual of Wildlife Diseases.” Unlike the previous printed versions of this publication, this new version is being developed as a “living“ electronic publication. Content will periodically be added and (or) updated as warranted, and it will always be reviewed by scientific experts (“peer reviewed”) before it is released. Thus, this publication will never be co
    By
    Water Resources, Ecosystems, National Wildlife Health Center

    Why bother about wildlife disease?

    In most developed countries, the maintenance of the numbers of wildlife1 is vested in the natural resource agencies of those countries. During earlier times, game species were the primary focus of natural resource agencies2,3 however, current wildlife conservation continues to transition towards a more holistic focus on biodiversity4 and environmental health5,6. Nevertheless, that transition lags
    By
    Ecosystems, National Wildlife Health Center

    Enhanced surveillance strategies for detecting and monitoring chronic wasting disease in free-ranging cervids

    The purpose of this document is to provide wildlife management agencies with the foundation upon which they can build scientifically rigorous and cost-effective surveillance and monitoring programs for chronic wasting disease (CWD) or refine their existing programs. The first chapter provides an overview of potential demographic and spatial risk factors of susceptible wildlife populations that may
    By
    Ecosystems, National Wildlife Health Center

    Chronic Wasting Disease

    Chronic wasting disease (CWD) is an always-fatal, neurological illness occurring in North American cervids (members of the deer family), including white-tailed deer, mule deer, elk and moose. Since its discovery in 1967, CWD has spread geographically and increased in prevalence locally. CWD is contagious; it can be transmitted freely within and among free-ranging populations. It is likely that dis
    By
    Ecosystems, National Wildlife Health Center

    Chronic Wasting Disease Positive Tissue Bank

    In 2005, the USGS National Wildlife Health Center entered into an agreement with the Wyoming Game and Fish Department and the Department of Veterinary Sciences at the University of Wyoming to produce a collection of positive tissues from cervids intentionally infected with chronic wasting disease. This agreement was facilitated through the University of Wyoming Cooperative Fish and Wildlife Unit.
    By
    Ecosystems, National Wildlife Health Center

    Disease emergence and resurgence—the wildlife-human connection

    In 2000, the Global Outbreak Alert and Response Network (GOARN) was organized as a global disease watchdog group to coordinate disease outbreak information and health crisis response. The World Health Organization (WHO) is the headquarters for this network. Understandably, the primary focus for WHO is human health. However, diseases such as the H5N1 avian influenza epizootic in Asian bird populati
    By
    Ecosystems, National Wildlife Health Center
  • News
    link

    Chronic Wasting Disease: Can Science Save Our Dear Deer?

    Chronic wasting disease is as ominous as it sounds for North American cervids.

    Read Article
    link

    New Approach May Detect Chronic Wasting Disease Earlier, at Less Cost

    A new statistical approach to disease surveillance may improve scientists’ and managers’ ability to detect chronic wasting disease earlier in white...

    Read Article
    link

    Chronic Wasting Disease in White-Tailed Deer

    Chronic wasting disease may have long-term negative effects on white-tailed deer, a highly visible and economically valuable keystone species...

    Read Article