Chronic Wasting Disease in Free Roaming Cervids in Saskatchewan and Alberta

Submitted to

Eliot Terry

BIO-163 CO-2

Lethbridge Community College

By

Richard Belchamber

November 28, 2006

ii

Abstract

In North America, elk (Cervus elaphus), mule (Odocoileus hemionus), and white-tailed

deer (Odocoileus virginianus) are dying from chronic wasting disease. Chronic wasting

disease in cervids is the equivalent to Mad Cow Disease in cattle although the form of

transmission is unknown. This disease affects more male deer than female deer and risk

of getting the disease increased with age. There are various signs of the disease in later

stages in infected animals such as drooling, depression, weight loss, disinterest in eating,

and eventual death. The disease was first discovered in a game farm in Colorado in 1967

and has escaped to the free-ranging population and is now found in Wisconsin, Nebraska,

and New Mexico. A separate outbreak (which may or may not have been connected to

the original outbreak) was found in Saskatchewan in an elk farm in 1996. The disease

somehow escaped into the free-ranging population of white-tailed deer and mule deer,

with a lower prevalence found in elk. Recent (2005) collected tests from Saskatchewan

Environment and Wisconsin Department of Natural Resources show an average chance

of getting with chronic wasting disease a deer in Saskatchewan is 0.9% while it is 0.7%

in Wisconsin. In both areas chronic wasting disease has been spreading for the last 5 to 6

years. Chronic wasting disease has been found in deer along the Alberta and

Saskatchewan border in 2006. Alberta has taken an aggressive stance on chronic wasting

disease by setting up herd reduction areas similar to those in Saskatchewan. These areas

are designated for hunter harvest surveillance in order to determine if chronic wasting

disease is spreading.

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Table of Contents

1 Introduction ................................................................................................................. 1

2 What is Chronic Wasting Disease............................................................................... 2

3 History of Chronic Wasting Disease........................................................................... 3

4 Current Plans for Chronic Wasting Disease in Canada .............................................. 5

5 A Comparative Analysis ............................................................................................. 6

5.1 CWD in Saskatchewan ....................................................................................... 7

5.2 CWD in Wisconsin ............................................................................................. 8

5.3 Analysis............................................................................................................... 9

6 CWD in Alberta ........................................................................................................ 10

7 What can Hunters do to Help fight Chronic Wasting Disease.................................. 11

8 Literature Citied ........................................................................................................ 13

9 Appendix A. Herd Reduction Areas and Zones required to deposit samples in

Saskatchewan .................................................................................................................... 17

10 Appendix B. Herd Reduction Zones and Disease Eradication Zones for 2006 in

Wisconsin .......................................................................................................................... 18

Figures and Tables

Table 1. Results of Recent CWD Tests in Saskatchewan ................................................... 7

Table 2. Results of Recent CWD Tests in Wisconsin ........................................................ 8

Figure 1. Locations in North America where CWD has been diagnosed ........................... 4

Figure 2. Percentage of CWD in Free-ranging population in Saskatchewan ..................... 8

Figure 3. Percentage of CWD in Free-ranging population in Wisconsin ........................... 9

Figure 4. CWD Herd Reductions Areas and the Voluntary Deer Head Submission zones

........................................................................................................................................... 10

1

1 Introduction

One of the most defining characteristics of the provinces of Saskatchewan and

Alberta are the vast grasslands areas in the south and the boreal forest to the north. In

both these areas a few of the common primary consumers are White-tailed deer

(Odocoileus virginianus), Mule deer (Odocoileus hemionus), and elk (Cervus elaphus)

which all stem from the Family Cervidae. For hundreds of years these animals have been

a keystone for various ecosystems in these two habitats and also an economic tool used

by government agencies and local businesses. These populations of these animals are

now in danger of chronic wasting disease (CWD) which had originally been discovered

in a research laboratory in Colorado in 1967, and has been fairly common in cervids

(members of the Cervidae family) in game farms and has escaped to the free-ranging

population(Miller and Williams 2002).

This disease is very dangerous because it is in the same family of virus as Mad

Cow disease which grew a strain that affects humans, but also because no animal has ever

survived after being diagnosed with the disease, and there are no known tests for CWD

while animals are alive (Miller and Williams 2002, Wisconsin Depart of Natural

Resources 2002). The disease also poses a large threat to local economies and

government agencies. The local ecosystem would be devastated by the lost of the cervids.

Various federal agencies are involved with the eradication and control such as the

Government of Canada, Health Canada, Parks Canada, Canadian Public Health Agency,

the United States Government, American Animal & Plant Health Inspection Service, and

United States Depart of Agriculture. Also various provincial and state agencies such as

Alberta Sustainable Resource Development, Saskatchewan Environment, and the

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Wisconsin Department of Natural Resources among others. And there are independent

researchers such as M.W. Miller, E.S. Williams, E.M. Schauber, A. Woolf, DA Grear

MD Samuel, J.A. Langenberg, and K. Delwyn as well as many others. And various non-

profit organizations like the Chronic Wasting Disease Alliance.

The aim of this paper is identify what CWD is, examine its history, compare how

it’s being handled in different places, to look where the disease is headed in Canada, and

what people can do to help fight the disease.

2 What is Chronic Wasting Disease

CWD is a transmissible neurological disease found in Cervids. It is classified as a

Transmissible Spongiform Encephalopathy (TSE), it is a disease from the same family as

Mad Cow disease in cattle, scrapie in sheep, and Creutzfeldt - Jakob disease in humans

(Wisconsin Department of Natural Resources 2002). The disease causes prions (proteins)

in the brain to convert brain cells into spongy cells. These cells cause microscopic holes

in the prion tissue in the brain which can eventually lead to death. These cells accumulate

on the brain, eyes, spinal cord, lymph nodes, tonsils, and spleen of the infected deer.

(Wisconsin Department of Natural Resources 2002) The prions in the muscle tissue in

infected cervids has also tested positive to CWD (Angers et al. 2006). In the later stages

of the disease, the degeneration of the cells causes some alterations observable in cervid

behavior, excessive salvation, loss in appetite, weight loss, loss of body control, and

eventual death. The disease seems to affect twice as many males than females, and the

chances increase of getting the disease with the age. (Grear et al. 2003)

It is the only known TSE to effect elk and deer (Miller & Williams 2002). To date

no animal (elk, white-tailed deer, mule deer) diagnosed with CWD has survived (Miller

3

and Williams 2002). Although it’s highly transmissible to other cervids it appears

domesticated animals such as cattle, sheep, and horses have a natural resistance to the

disease and can only contract the disease if it is inserted manually into the brain where

the effects are very similar to the effects in cervids (Miller & Williams 2002). Free-

ranging elk have a much lower prevalence with CWD than mule deer and especially

white-tailed deer (Hlady 2006, Program Manager for CWD in the province of

Saskatchewan, pers. comm.). How the disease is transmitted from animal to animal is still

unknown, but Schauber and Woolf (2003) believe that the disease is transmitted through

bodily fluids via direct and indirect contact. This theory is supported by the excessive

transmission of the disease within the game farm population (high population in a

confined space) and in free ranging cervids (through migratory paths, and grouping

together in the winter months). It explains why the captive populations of animals have

been devastated far more than the free-ranging population.

A study preformed in the Disease Eradication Zone in 2002-2003 by Grear et Al.

(2006) in Wisconsin gave some insight on the incubation period of the disease. The

previous studies have shown the incubation period for CWD was 1.5 years or more

(Miller and Williams 2002), but Grear et al. (2003) results have 5 out of 1021 fawns

tested for CWD tested positive in 2002. Three of the 5 were about 5 months old while

the other two were 9 months and 10 months old respectively. This puts the disease

incubation period to possible birth. There is no known test for CWD while an animal is

alive (Miller and Williams 2002).

3 History of Chronic Wasting Disease

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In 1967, the disease that came to be known as Chronic Wasting disease was first

discovered in a research facility in Northern Colorado in a captive mule deer. It wasn’t

until 1978 the disease was recognized as TSE. In 1981, the first case of CWD in a free-

ranging animal was an elk in Colorado. In 1983, the first-hunter harvest surveillance was

first initiated. The technique is set in which hunters are allowed to kill cervids in a certain

hunting zones coordinated by the government agencies as long the heads of the down

animals are sent in for testing and is the technique currently in use today. In 1985, there

was the first confirmed case of CWD in free-ranging mule deer. In 1990, there was the

first confirmed case of CWD in free-ranging white-tailed deer. In 1996, the first case of

CWD was found in elk in a game farm in Saskatchewan (Chronic Wasting Disease

Alliance 2006).

In 2000/2001, the first diagnostic of CWD in free-ranging mule deer in

Saskatchewan with indications that it may have been transmitted from an elk affect with

CWD from a game farm. In 2001, a diagnostic of an elk imported to Korea from Canada

tested positive for CWD. That same year there is massive depopulation of elk in game

farms in Saskatchewan due to CWD while the USDA declares an animal emergency due

to CWD in elk farms. By 2002, CWD has been found in free-ranging deer populations in

Nebraska, Wisconsin, and in New Mexico. (Chronic Wasting Disease Alliance 2006) In

early 2006, CWD has been found in free-ranging cervids in Alberta along the

Saskatchewan/ Alberta border. (Alberta Sustainable Resource Management 2006)

Figure 1. Locations in North America where CWD has been diagnosed

(Chronic Wasting Disease Alliance 2006)

5

4 Current Plans for Chronic Wasting Disease in Canada

In October of 2005, the Government of Saskatchewan published the paper, Canada’s

National Chronic Wasting Disease Control Strategy on behalf of the Inter-Agency

Oversight Committee. According to this paper, Canada has 6 goals in order to control

CWD inside its border:

1. Prevention of further emergencies of CWD in new locations, new prions

emerging, or affecting new species.

This involves the control of importation and exportation of Cervids and

cervid parts interprovincial, intraprovincial, and also the international.

Also includes using updated and effective scientific research.

2. Early detection of CWD in cervid populations.

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Includes creating a national network of CWD and laboratory diagnosis

which will have rapid and complete analysis so it may be distributed to all

participating parties.

3. Planned responses to CWD

Control planning to Contain, Reduce, and eventually Eradicate the disease

in areas where it already exists, while planning in advance for future

occurrences.

4. Effective Management of CWD

Includes scientific research on CWD and various mangament efforts and

appraisal.

Cost, risk, and Feasibility analysis on such plans.

Disease Surveillance programs will need to be evaluated

5. Education and Training

Education of field personnel, scientists

6. Communication

In between all sectors to achieve coordination and a collaboration

5 A Comparative Analysis

The CWD problem in Saskatchewan is somewhat of an isolated event compared to

the situation in Wisconsin, USA. The problem in Wisconsin is in fact a part of the larger

7

initial outbreak originally started in Colorado that has spread to surrounding states

including Wyoming, Nebraska, New Mexico, Illinois, and Utah (Grear et. al 2003).

To compare the situation and to get an understanding of the progression of the

disease in Saskatchewan we will compare Saskatchewan’s situation to the situation in

Wisconsin.

5.1 CWD in Saskatchewan

Table 1. Results of Recent CWD Tests in Saskatchewan

(Saskatchewan Environment 2005, Saskatchewan Environment 2006)

Year

White-Tailed Deer

Collected

Mule Deer

Collected Elk

Collected

Total Usable

Samples Negative

Tests Positive

Tests

2000 726 185 89 1000 999 1

2001 2294 1232 340 3866 3865 1

2002 2439 3386 185 6010 6000 10

2003 1876 2784 149 4809 4787 22

2004 1399 5255 0 6654 6620 34

2005 1509 3075 56 3691 3651 35

In 2000, out the 1000 usable cervid samples collected, only 1 sample tested

positive for CWD. In 2001, out of the 3,866 samples collected, again only 1 sample had

tested positive. In 2002, out of the total 6,010 usable cervid samples, 10 tested positive

for CWD. In 2003, out of the total 4,819 usable cervid samples, 22 tested positive for

CWD. In 2004, out of the total 6,654 usable cervid samples, 34 tested positive for CWD.

In 2005, out of the total 3,691 usable cervid samples, 35 tested positive for CWD

(Saskatchewan Environment 2005, Saskatchewan Environment 2006). These samples

were collected from the mandatory sample collection zones. (See figure 2.) One of the

highest concentrations of CWD in white-tailed deer is zone 50, near Nipawin, where the

probability of getting a deer with CWD is 2%. (Hlady 2006, Program Manager of CWD

8

in Saskatchewan, pers. comm.) Saskatchewan typically has a larger area with a lower

concentration of cervid populations.

Figure 2. Percentage of CWD in Free-ranging population in Saskatchewan

Based on results retrieved from Saskatchewan Environment

Percentage of CWD in Free-ranging population

0.00000

0.00200

0.00400

0.00600

0.00800

0.01000

2000 2001 2002 2003 2004 2005

Years

Po

pu

lati

on

(%

)

Percentage of

CWD in Free-

ranging

population

5.2 CWD in Wisconsin

Table 2. Results of Recent CWD Tests in Wisconsin

(Wisconsin Department of Natural Resources website 2006)

Year

Total Samples Collected

Total Usable

Samples

Negative Test

Results Positive

Tests

1999-2001 1091 1091 1088 3

2002 40170 40133 39928 205

2003 14901 14901 14784 117

2004 19199 19195 19050 145

2005 24803 24797 24616 181

In the years 1999 to 2001, 1091 usable samples where collected 3 cervids tested

positive for CWD. In 2002, out of the 40,133 total usable samples collected 205 cervids

tested positive for CWD. In 2003, out of the 14,901 total usable samples collected 117

cervids tested positive for CWD. In 2004, 19,195 samples were collected tested and 145

tested positive for CWD. In 2005, 24,797 total testable samples were collected and 181

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cervids tested positive for CWD (Wisconsin Department of Natural Resources 2006). The

landscape in Wisconsin is smaller with a much higher concentration of deer.

Figure 3. Percentage of CWD in Free-ranging population in Wisconsin

Based on results retrieved from Wisconsin Department of Natural Resources

Percentage of CWD in Free-ranging population

0

0.001

0.002

0.003

0.004

0.005

0.006

0.007

0.008

0.009

1999-

2001

2002 2003 2004 2005

Years

Po

pu

lati

on

(%

)

Percentage of CWD in

Free-ranging population

5.3 Analysis

We have two very different situations in these two places. In Wisconsin we have a

high density area, with an equally high population. The results of the CWD hunter-

harvest surveillance in Wisconsin were 3 to 4 times larger than the results of CWD

hunter-harvest surveillance in Saskatchewan. Samples are required from zones 5, 8 to 14,

19, 23 to 26, 43, 45 to 47, 50, 53, 62, 63, 67 , 68 while there are positive test results from

Zones( and thusly Herd Reductions Areas): 12, 13, 14, 46, 47, 50.

For the year 2005, Wisconsin had 24,797 usable samples with 181 positive tests. In

the same year for Saskatchewan, there were 3,691 testable samples with 35 positive tests.

So in 2005, the average percentage of getting an animal with CWD is 0.7% in Wisconsin,

while the average percentage of getting an animal with CWD in Saskatchewan is 0.9%

(varies with location). These results are very troubling due to the current rate of CWD in

Saskatchewan and Wisconsin seems to be spreading. (See Figures 3 & 5)

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6 CWD in Alberta

Models of CWD epidemic dynamics suggest an early aggressive intervention via selected

culling and an increase of generalized population reduction has shown the best possible

results of preventing the establishment of CWD (Miller and Williams 2002). Alberta’s

strategy has taken this fact and has applied it to its policies creating an aggressive CWD

border plan. (Alberta’s Sustainable Resource Management 2006) Along the

Saskatchewan and Alberta border there are three confirmed outbreaks of CWD. (See

Figures 2 and 6) Currently there are three Herd Reduction Areas in Alberta in hunting

zones; 150, 151, 234. Then there are compulsory Head submission zones (zones 150,

151, 234, 256, 500) and the voluntary head submission zones in Alberta (zones 152, 144,

148, 162, 200, 202, 203, 232, 238, and 236) Alberta recently opened the Herd Reduction

Areas this January to March and in that time they collected and tested 1688 deer (1475

mule deer, 213 white-tailed deer), 9 tested positive for CWD (Alberta’s Sustainable

Resource Development 2006).

Figure 4. CWD Herd Reductions Areas and the Voluntary Deer Head Submission zones

(Alberta’s Sustainable Resource Development 2006)

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7 What can Hunters do to Help fight Chronic Wasting Disease

Through various government agencies in the Provinces and States that have been

affected by CWD, their main weapon against the disease has been the hunter-harvest

surveillance. This depends solely upon the hunters, who can participate by going to

various government instillations and getting Herd Reduction tags/ CWD control tags

(Alberta, Saskatchewan, Wisconsin, etc.) or Disease Eradication tags (Wisconsin, and

other American states), as long any and all cervids that are killed in those areas have their

heads sent in for testing. Most of these agencies are in accordance in how people should

handle the downed animals. Avoid handling the areas where CWD usually accumulates

12

such as; the brain, lymph nodes, eyes, spinal cord, tonsils, and spleen. (Wisconsin

Department of Natural Resources 2002)

These agencies do not accept animals with antlers so care must be taken when

removing the antlers from the skull. If any brain tissue is exposed put a paper towel over

it and don’t handle it as it is required for testing. (Saskatchewan Environment 2005) The

various agencies (Alberta’s Sustainable Resource Development, Saskatchewan

Environment, etc.) require some additional information about such as the time, date,

hunting zone you were killed the animals, and the GPS co-ordinates of where the animal

was killed. (Saskatchewan Environment 2005) All these agencies advise wearing latex

gloves when handling the dead animal, and advise against eating the meat of an animal

being sent for testing until the results are posted on the government agencies

website.(Wisconsin Department of Natural Resources 2002, Saskatchewan Environment

2005) A recent of study of CWD in cervids show that infected cervids may have infected

prions in their muscle tissue and may be transmissible to humans in this form. (Angers et

al. 2006)

Hunter/harvest surveillance is essential to the tracking and studying of CWD. It gives

us usable samples for examination of the disease and guides to see if the disease is

spreading and if our efforts are effective. Currently in Saskatchewan there are indications

that the disease is still spreading. (Hlady 2006, Program manager of CWD in

Saskatchewan, pers. comm.) But with the help of the hunter harvest surveillance and the

coordination of government agencies and independent researchers come new studies and

new technologies in the hopes of containing and eventually eliminating the disease.

13

8 Literature Citied

Alberta’s Sustainable Resource Development. 2006. Chronic Wasting Disease Alberta-

Saskatchewan 2006 Border Program Overview. Alberta’s Sustainable Resource

Development, Edmonton, Alberta. Retrieved 15 October 2006 from

http://www.srd.gov.ab.ca/fw/pdf/2006_AB_Sask_border_prg.pdf.

Angers R.C., Browning S.R., Seward T.S., Sigurdson C.J., Miller M.W., Hoover E.A.,

Telling G.C. 2006. Prions in Skeletal muscles of Deer with chronic wasting

disease. Science 311 (5768):1117. Retrieved 2 November 2006, from

Chronic Wasting Disease Alliance. 2006. Chronic Wasting Disease. Pyron Technologies,

Inc., N/A. Retrieved 4 October 2006 from http://www.cwd-

info.org/index.php/fuseaction/about.map.

Grear DA, Samuel MD, Langenberg JA, Delwyn K. 2006. Demographic patterns and

harvest vulnerable of chronic wasting disease infected white-tailed deer in

Wisconsin. Journal of Wildlife Management 70(2):546-553

Miller MW, Williams ES. 2002. Chronic Wasting Disease in deer and elk in North

America. Revue scientifique et technique (International Office of Epizootics)

21(2): 306-316. Retrieved 4 October 2006 from National Center for

Biotechnology Information database.

Mothwing camo technologies. 2006. Mothwing Camo Technologies Camouflage Patterns

and Products. Mothwing Camo Technologies, Helenwood, Tennessee. Retrieved

27 October 2006 from http://www.mothwingcamo.com/images/White-tailed-

Deer-L.jpg

Saskatchewan Environment. 2005. Canada’s National Chronic Wasting Disease Control

Strategy. Saskatchewan Environment, Regina, Saskatchewan. Retrieved 16

October 2006 from http://www.se.gov.sk.ca/fishwild/NCWDCS2005.pdf.

Saskatchewan Environment. 2006. Provincial Summary of CWD Test Results.

Saskatchewan Environment, Regina, Saskatchewan. Retrieved 4 October 2006

from http://wildlife1.usask.ca/cwd/provincial_summary.php.

Saskatchewan Environment. 2006. Chronic Wasting Disease 2006 Management Program.

Saskatchewan Environment, Regina, Saskatchewan. Retrieved 4 October 2006

from

http://www.se.gov.sk.ca/fishwild/Chronic%20Wasting%20Disease%202006%20

Management%20Program.pdf.

14

Saskatchewan Environment. 2005. Chronic Wasting Disease Management Program Fall

2005. Saskatchewan Environment, Regina, Saskatchewan. Retrieved 4 October

2006 from http://www.se.gov.sk.ca/fishwild.

Schauber EM, Woolf A. 2003. Chronic Wasting Disease in elk and deer: a critique of

current models and their application. Wildlife Society Bulletin 31(3):610-616.

Pybus MJ. 2006. Alberta’s Chronic Wasting Disease Management Programs in 2006 and

upcoming surveillance. Alberta’s Sustainable Resource Development, Edmonton,

Alberta. Retrieved October 22 2006 from

http://www.srd.gov.ab.ca/fw/diseases/CWD/pdf/2006%20CWD%20report%20an

d%20upcoming%20surveillance.pdf

Veterinary Services. 2002. Chronic Wasting Disease. Animal & Plant Health Inspection

Service, United States Department of Argiculture. Retrieved 15 October 2006

from http://www.aphis.usda.gov/lpa/pubs/fsheet_faq_notice/fs_ahcwd.html

Wisconsin Department of Natural Resources . 2002. Understanding Chronic Wasting

Disease in Wisconsin. Wisconsin Department of Natural Resources, Madison,

Wisconsin. Retrieved 23 October 2006 from

http://www.dnr.state.wi.us/org/land/wildlife/whealth/issues/CWD/doc/cwdbook

.pdf.

Wisconsin Department of Natural Resources . 2006.2006 CWD Zones Special

Regulations. Wisconsin Department of Natural Resources, Madison, Wisconsin.

Retrieved 23 October 2006 from

http://www.dnr.state.wi.us/org/land/wildlife/whealth/issues/CWD/doc/cwdbook

.pdf.

15

Secondary Citation

Miller MW, Thorne ET, Williams ES. 2002. Chronic Wasting Disease: Implications and

Challenges for Wildlife Management Presented at the 67th North American

Wildlife and Natural Resource Conference. S Williams, technical coordinator.

Proceedings of special session 1 on Wildlife Diseases: Crying Wolf or Crying

Shame?. N/A

16

Personal Communication

Hlady M. 2006. Personal interview, 3 November. Program manager of CWD for the

province of Saskatchewan, Regina, Saskatchewan.

17

9 Appendix A. Herd Reduction Areas and Zones required to deposit samples in Saskatchewan

Based upon results from Saskatchewan Environment

18

10 Appendix B. Herd Reduction Zones and Disease Eradication Zones for 2006 in Wisconsin

(Wisconsin Department of Natural Resources 2006)