U.S. Department of the Interior

U.S. Geological Survey

USGS-NWHC Information Sheet 

February 2003

providing easily accessible information to 

cooperators and the public – but much still 

needs to be done. New initiatives, based 

on the plans already developed, will seek 

to refine our information about the disease 

and identify effective management strategies for CWD control and eradication.

National Planning and Surveillance 

Workshop

The USGS National Wildlife Health 

Center conducted a workshop in early 

December, 2002, to develop strategies 

for detection and surveillance of Chronic 

Wasting Disease (CWD) in wild deer 

and elk. Participants came from various 

backgrounds (e.g. wildlife disease, cervid 

population biology, statistical modeling) 

and provided differing viewpoints and 

expertise, resulting in a comprehensive 

plan addressing many facets of the 

problem. A white paper is anticipated 

in late March and will be available in 

both electronic and hard copy form. The 

intended audience includes state and 

federal wildlife management agencies, 

tribal governments, and wildlife disease 

investigation and research programs. 

The group identifi ed three primary goals 

for a surveillance program: detection, 

assessment, and monitoring. Several risk 

factors were suggested to guide decisions 

of resource allocation and focus on target 

areas. Sampling design was determined 

based upon several likely scenarios of 

population size, species, and habitat. 

Strengths and weaknesses of several 

sample collection methods were evaluated. 

Implementation costs for large protracted 

surveillance programs were estimated 

Helping to Combat Chronic 

Wasting Disease

Collaborative efforts to address the 

problem of CWD – in Wisconsin and 

across the country – have provided some 

answers, but much still needs to be done.

Background

Chronic Wasting Disease (CWD) is a 

disease of the nervous system that results 

in distinctive lesions in the brain. CWD 

affects elk, white-tailed deer, and mule 

deer, but has not been documented in livestock or humans. The cause is unknown 

and no treatment is available. Infected deer 

and elk can appear robust and healthy in 

the early stages of CWD; it may take several years before they show clinical signs, 

after which the disease is fatal. Direct 

contact between infected and non-infected 

animals is the most likely route of transmission, but other possibilities are under 

consideration, including contamination of 

soil by excreta from infected animals.

USGS is collaborating with federal, state, 

and private partners to address CWD 

issues. These joint efforts have addressed 

immediate needs – developing cooordinated plans, establishing diagnostic capabilities to identify the disease, modeling 

and analyzing effects of the disease, and 

based on the varied experience of the 

workshop participants. 

Wisconsin Veterinary Diagnostic 

Laboratory Collaboration

In cooperation with the Wisconsin 

Veterinary Diagnostic Laboratory, USGS 

has established a shared diagnostic 

laboratory for the detection of CWD in 

deer and elk tissues. This capability allows 

USGS to provide diagnostic support to the 

Department of Interior for this disease. 

Both the gold standard detection test and 

the high throughput test are employed. 

In addition, USGS pathology staff have 

participated in USDA sponsored training 

sessions, to allow them to accurately 

interpret results from these tests. 

Wisconsin Department of Natural 

Resources Partnership

USGS has had a sustained role in the 

investigation of CWD in Wisconsin. 

Initially, the Center provided general 

information, consultation and assistance to 

state personnel. Staff provided guidance 

on surveillance plans, and analyses of 

results collected by implementation of 

the recommended plans. These analyses 

proved crucial to the continued assessment 

of the disease in the state. 

USGS staff have continued to participate 

in team meetings on the overall Wisconsin 

state CWD program. Personnel are active 

participants on the Science and Health 

Team and the Research Team, providing 

comments, suggestions, and direct input 

into decisions. USGS staff also assisted 

with questions from the public at 6 

public hearings on CWD held throughout 

the state. In addition, staff members 

Preparing to sample lymph nodes for CWD 

testing at the Park Falls, Wisconsin, sampling 

site. Photo courtesy of Harold Rihn, Jr., USGS.

Elk. Photo courtesy of Milton Friend, USGS.
participated in special deer harvests 

as part of the state-sponsored disease 

control program and worked in the tissue 

processing centers, offering their expertise 

to accurately collect appropriate tissues for 

the detection of CWD. 

Department of Interior and State 

Activities

USGS has been contacted by several 

Bureaus within the Department for 

assistance with CWD. In addition, tribal 

governments — either through the Bureau 

of Indian Affairs or directly — have asked 

for training and assistance in surveillance 

programs. The Fish and Wildlife Service 

has requested and been given advice and 

assistance in establishing monitoring 

programs as well. 

USGS scientists from the National 

Wildlife Health Center represented the 

Department of Interior and participated 

in a review of the science program 

proposed by the state of Colorado for the 

management of CWD. Review fi ndings 

were presented at a two day workshop 

in Denver, Colorado. Scientists also 

participated, by invitation, in a workshop 

hosted by the Agricultural Research 

Service of the USDA, which focused on 

prion diseases including CWD. USGS 

scientists served as panelists in a special 

session devoted to CWD at a meeting 

of the United States Animal Health 

Association in St. Louis, Missouri. Most 

imporantly, USGS personnel actively 

participated in the development of the 

National Plan for the Investigation of 

CWD and later in the implementation 

plans for states, tribes and federal 

agencies.

Printed on recycled paper

Information Products

USGS personnel have worked diligently 

to provide accurate, up-to-date 

information on CWD, providing links 

to federal, state, foreign and private 

organizations’ information on a web site 

at www.nwhc.usgs.gov, with media links, 

factsheets, planning documents, a CWD 

bibliography, questions and answers, and 

regularly updated maps showing the extent 

of the disease. In addition, the newly 

inaugurated Wildlife Disease Information 

Node (WDIN) was initiated as part of 

the National Biological Information 

Infrastructure to serve as a focal point 

for information on diseases in wild 

animals, offering near real-time prevalence 

reporting. A strong initial focus will be 

on Chronic Wasting Disease, where all 

current web based information will be 

organized and annotated. The WDIN will 

also serve as a central repository for CWD 

testing results generated by state, tribal 

and federal agencies.

New Initiatives and Future Directions

Collaborative research studies with 

the Wisconsin DNR and University of 

Wisconsin have been initiated to enhance 

scientifi c knowledge about CWD and to 

assist in the development of management 

strategies. Research focuses on better 

understanding how CWD is transmitted 

among white-tailed deer, understanding 

the pattern of infection on the landscape, 

and determining the susceptibility of 

different age/sex classifi cations of deer to 

infection. Results will be used to develop 

improved modeling and quantitative tools 

to help predict the spread of CWD and 

help evaluate management actions 

For more information on Chronic Wasting 

Disease, please contact Dr. Scott Wright, 

USGS National Wildlife Health Center, 

(608) 270-2460, or Mr. Paul Slota, USGS 

National Wildlife Health Center, (608) 

270-2420. Mule Deer. Photo courtesy of B. Gill.

White-tailed deer fawn. Photo courtesy of 

Wellesley College.

to control or eradicate this disease. 

Collaborative research studies at Iowa 

State University have been initiated to 

assist in developing statistical tools to 

improve and assess surveillance programs 

that will be employed to determine if 

CWD is present on the landscape, assess 

the distribution and prevalence of new 

disease foci, and to monitor changes in 

disease prevalence in established disease 

areas.

Technical assistance for state agencies 

and units of the FWS that might become 

affected by CWD is expected to increase 

in 2003. USGS scientists in the Central 

Region are planning to investigate the 

relationship of deer and elk population 

ecology to CWD as a basis for future 

management recommendations.

A better understanding of the dynamics 

of the disease is critical to effective 

management strategies. The ongoing 

collaboration between federal, state 

and tribal governments, and private 

organizations, offers the best possibility 

of identifying disease parameters and 

developing successful control measures.