Occurrence

As of September 2017, CWD in free-ranging deer, elk and/or moose has been reported in at least 21 states in the continental United States, as well as two provinces in Canada. In addition, CWD has been reported in reindeer and moose in Norway, and a small number of imported cases have been reported in South Korea. The disease has also been found in farmed deer and elk.

CWD was first identified in captive deer in the late 1960s in Colorado and in wild deer in 1981. By the 1990s, it had been reported in surrounding areas in northern Colorado and southern Wyoming. Since 2000, the area known to be affected by CWD in free-ranging animals has increased to at least 21 states, including states in the Midwest, Southwest, and limited areas on the East Coast. It is possible that CWD may also occur in other states without strong animal surveillance systems, but that cases haven’t been detected yet. Once CWD is established in an area, the risk can remain for a long time in the environment. The affected areas are likely to continue to expand.

Nationwide, the overall occurrence of CWD in free-ranging deer and elk is relatively low. However, in several locations where the disease is established, infection rates may exceed 10 percent (1 in 10), and localized infection rates of more than 25 percent (1 in 4) have been reported. The infection rates among some captive deer can be much higher, with a rate of 79% (nearly 4 in 5) reported from at least one captive herd.

Chronic Wasting Disease Among Free-Ranging Cervids by County,United States, September 2017

As of September 2017, there were 181 counties in 21 states with reported CWD in free-ranging cervids.

Arkansas

1. Boone
2. Carroll
3. Madison
4. Marion
5. Newton
6. Pope
7. Searcy

Colorado

1. Boulder
2. Douglas
3. Eagle
4. El Paso
5. Grand
6. Jackson
7. Jefferson
8. Larimer
9. Logan
10. Mesa
11. Moffatt
12. Morgan
13. Phillips
14. Pueblo
15. Rio Blanco
16. Routt
17. Sedgwick
18. Summit
19. Weld
20. Yuma

Illinois

1. Boone
2. Dekalb
3. DuPage
4. Grundy
5. Jo Daviess
6. Kane
7. Kankakee
8. Kendall
9. Lake
10. LaSalle
11. Livingston
12. McHenry
13. Ogle
14. Stephenson
15. Will
16. Winnebago

Iowa

1. Allamakee
2. Clayton

Kansas

1. Cheyenne
2. Decatur
3. Ellis
4. Ford
5. Graham
6. Gray
7. Grove
8. Hodgeman
9. Jewell
10. Kearny
11. Logan
12. Meade
13. Norton
14. Pawnee
15. Phillips
16. Rawlins
17. Scott
18. Sheridan
19. Sherman
20. Smith
21. Stafford
22. Thomas
23. Trego
24. Wallace

Maryland

1. Allegany

Michigan

1. Clinton
2. Ingham

Minnesota

1. Fillmore
2. Olmsted

Missouri

1. Adair
2. Cole
3. Franklin
4. Jefferson
5. Linn
6. Macon
7. St. Clair

Nebraska

1. Arthur
2. Banner
3. Boone
4. Box Butte
5. Buffalo
6. Cass
7. Cherry
8. Cheyenne
9. Custer
10. Dawes
11. Deuel
12. Furnas
13. Garden
14. Grant
15. Hall
16. Harlan
17. Hitchcock
18. Holt
19. Hooker
20. Keith
21. Kimball
22. Lincoln
23. Lancaster
24. Loup
25. Morrill
26. Nance
27. Phelps
28. Polk
29. Red Willow
30. Saline
31. Scotts Bluff
32. Sheridan
33. Sioux
34. Thayer
35. Webster

New Mexico

1. Dona Ana
2. Otero
3. Socorro

New York

1. Oneida

North Dakota

1. Grant
2. Sioux

Pennsylvania

1. Blair
2. Bedford
3. Cambria
4. Clearfield
5. Fulton

South Dakota

1. Custer
2. Fall River
3. Lawrence
4. Pennington

Texas

1. Dallam
2. El Paso
3. Hartley
4. Hudspeth
5. Medina

Utah

1. Daggett
2. Grand
3. San Juan
4. Sanpete
5. Uintah
6. Utah

Virginia

1. Frederick
2. Shenandoah

West Virginia

1. Hampshire
2. Hardy

Wisconsin

1. Adams
2. Crawford
3. Columbia
4. Dane
5. Grant
6. Green
7. Iowa
8. Jefferson
9. Juneau
10. Kenosha
11. Lafayette
12. Portage
13. Racine
14. Richland
15. Rock
16. Sauk
17. Walworth
18. Washburn
19. Waukesha

Wyoming

1. Albany
2. Big Horn
3. Carbon
4. Converse
5. Crook
6. Goshen
7. Hot Springs
8. Johnson
9. Laramie
10. Lincoln
11. Natrona
12. Niobrara
13. Platte
14. Sheridan
15. Washakie
16. Weston