1. Diseases & Causative Agents
Infectious Diseases
Viral
Prion
Bacterial
Protozoal
Parasitic

2. Diseases & Causative Agents
Non-Infectious Diseases
Chemical
(pesticide, heavy metals, contaminants)
Physiological
Genetic
Nutritional
Trauma

3. A H
Ex: Influenza
Agent Increased E A H
Good Health
“In Balance” A H
Ex: Tularemia, Plague
Host pop. increased

4. A H A H
Ex: Air Pollution
Environment upset &
makes host more
susceptible
Ex: Flood
-Environment upset &
promotes growth of agent
(typhoid fever, cholera)

5. Diseases & Causative Agents
Disease Transmission
Direct: usually within spp.
Indirect: through different spp.

6. Diseases & Causative Agents
Contagious – transmittable to others
All contagious diseases are infectious
Contagious Infectious (not contagious)
cold tetanus

7. Diseases & Causative Agents
Chronic: slow-acting to overcome resistance of host (long-term)
Acute: short-term, agent overwhelms host rapidly
Subclinical: don’t develop clinical signs of disease

8. Diseases & Causative Agents
Pathogenic: ability of agent to induce disease
Virulence: severity of disease produced by agent
e.g., common cold very pathogenic, not virulent
rabies = not very pathogenic, very virulent

9. Wildlife Diseases Interest from wildlife management point-of-view:
Domestic and/or wild animals can serve as reservoirs and/or vectors
Density of wildlife populations

10. Wildlife Diseases Interest from human health & safety point-of-view:
Domestic and/or wild animals can serve as reservoirs and/or vectors
e.g., avian influenza
Since 2003, 393 human cases, 248 deaths (WHO)

11. Wildlife Diseases
Interest from pet/domestic animal health & safety point-of-view:
Domestic and/or wild animals can serve as reservoirs and/or vectors
e.g., bovine TB (Mycobacterium bovis)

12. Wildlife Diseases Interest from wildlife management point-of-view:
Density of wildlife populations
DD response?
Red Grouse & strongylosis (caused by Trichostrongylus tenuis)
Lack’s rebuttal [food supply & weakened state of birds]

13. Wildlife Diseases Interest from wildlife management point-of-view:
Small populations, threatened/endangered spp.

14. Wildlife Diseases Interest from wildlife management point-of-view:
Small populations, threatened/endangered spp.
1984 Patuxent Wildlife Research Center, 7 of 39 whooping cranes (18% of captive breeding flock) die of possible insect-borne virus

15. Wildlife Diseases Interest from wildlife management point-of-view:
Part of community dynamics
Newfoundland, lynx biting caribou calves, transfer Pasteurella multocida in saliva via bites
27% calf survival before lynx removal
63% calf survival after lynx removal

17. Wildlife Diseases Wildlife management responses: Culling
Stanislaus Nat’l Forest (CA) , 22,000 mule deer killed in response to foot-and-mouth outbreak in cattle
10% of these showed lesions

18. Wildlife Diseases Wildlife management responses:
Monitor and “Clean up”/Contain
e.g., avian botulism

20. CWD

21. CWD Captive and wild cervids
white-tailed deer
mule deer
elk
moose
First observed, 1967, Colorado Division of Wildlife’s Research Facility in Fort Collins, CO (initially thought to be malnutrition)
1977 CWD determined to be TSE (mule deer)
1981, 1st wild animal (elk) from Rocky Mt. Nat’l Park, diagnosed
Models suggests may have been present in free-ranging populations of mule deer for more than 40 years

22. CWD Susceptibility of other cervids to CWD not known
Cattle and other domestic livestock appear to be resistant to natural infection (research continues)
Privately owned cervid facilities (POC) may allow spread

23. USDA APHIS WS National Wildlife Research Center (NWRC)
Congressional appropriations for research and management of CWD (and many other conflict issues)
Dr. Kurt VerCauteren

24. CWD in WI Discovered wild deer in 2001/2002 >700,000 deer hunters
Avg 460,000 deer harvested
Generates >$500 million retail
~$1 billion impact to state’s economy

25. CWD in WI Discovered wild deer in 2001/2002
Spent $40+ million testing and drastically reducing deer populations since
Initially planned to kill all estimated 30,000 deer in focal area
Saskatchewan spent $30+ million

26. CWD in WI

27. CWD in WI

28. CWD in WI

29. CWD in WI

30. CWD in WI

31. CWD in WI Surveillance program to detect 1% prevalence
Difference in age/gender
0.16% fawns +
Increase prevalence with age (faster in males)
2-3% yearlings +
2+ yrs (M = 10%, F = 4-5% +)

32. CWD in Michigan
Michigan : Michigan's First Case of Chronic Wasting Disease Detected at Kent County Deer Breeding Facility Date: August 25, 2008
Source: Michigan Department of Natural Resources LANSING - The Michigan departments of Agriculture (MDA) and Natural Resources (DNR) today confirmed the state's first case of Chronic Wasting Disease (CWD) in a three-year old white-tailed deer from a privately owned cervid (POC) facility in Kent County. The state has quarantined all POC facilities, prohibiting the movement of all - dead or alive - privately-owned deer, elk or moose. Officials do not yet know how the deer may have contracted the disease. To date, there is no evidence that CWD presents a risk to humans.

33. CWD in Michigan
Michigan : Tests of More Than 1,000 Deer Find No More Cases of Chronic Wasting Disease Date: October 07, 2008
Source: The Grand Rapids Press Statewide, 1,095 deer have been tested, with 964 testing clean and 131 awaiting results. More than 300 wild Kent County deer have been tested and found to be clear of chronic wasting disease after the highly contagious disorder was found in one northern Kent County farm-raised deer in August.
Approximately $1 million spent on testing