What is chronic wasting disease?
Chronic wasting disease (CWD) is an always fatal neurological disease that affects cervid species including deer, elk, caribou, and moose and was first recognized in mule deer at a Colorado research facility in 1967. CWD is part of the transmissible spongiform encephalopathy (TSE) family of diseases that includes Bovine Spongiform Encephalopathy (BSE), or Mad Cow Disease, in cattle; Creutzfeldt-Jakob disease (CJD) in humans; and Scrapie in sheep and goats. Infectious CWD prions cause misfolding in normal prion proteins leading to a chain reaction that results in sponge-like holes in the brain.
CWD transmission can occur directly through animal-to-animal contact or indirectly through prion-contaminated environments. Animals infected with CWD spread infectious prions through saliva, urine, and feces. Additionally, the carcass of an infected animal can contribute to environmental contamination. Once prions are in the environment, they can be infectious for years.
CWD infected animals may not show clinical signs of disease for up to 18 to 24 months post-infection. During this period, animals may look healthy but are infectious and spreading the disease. Clinical signs of late stage CWD include lowered head, lowered ears, progressive weight loss, rough hair coat, excessive salivation, excessive thirst, excessive urination, and other behavioral changes including stumbling and lack of fear of humans. However, most animals infected with CWD are more likely to die from other causes prior to reaching this stage.
Why should I care about CWD?
CWD is always fatal and any cervid infected with the disease will die. Research shows CWD-infected deer have a lower survival rate, and as a result, CWD can decrease deer populations over time. This can result in reduced hunting opportunities and is a threat to healthy deer populations and wildlife conservation in Pennsylvania.
Currently, there is no evidence that CWD is transmissible to humans or livestock. However, research conducted on CWD has demonstrated that it can pass through the digestive tract of scavengers and predators and remain infectious; plants can uptake CWD prions and remain infectious; soils retain infectious CWD prions for years; and water sources can be contaminated with CWD prions. Emerging CWD strains suggest higher potential for infections in other species.
People regularly encounter deer and consume venison as hunting is the largest source of mortality for deer in Pennsylvania. There is still much to learn about prion diseases, but given our knowledge of CWD, limiting wildlife, domestic animal, and human exposure to a known pathogen that has no treatment, vaccine, or cure is crucial. The Pennsylvania Department of Health, Centers for Disease Control and Prevention (CDC), and World Health Organization (WHO) recommend human exposure to CWD prions be avoided and people not consume a known or suspect CWD positive animal.
Where has CWD been found in Pennsylvania?
CWD was first detected in Pennsylvania at a captive facility in Adams County in 2012. Shortly after, three free-ranging CWD-positive deer were detected in Bedford and Blair counties. Since the first detections in 2012, CWD has been detected in the following counties: Adams, Armstrong, Bedford, Blair, Cambria, Clearfield, Cumberland, Dauphin, Franklin, Fulton, Huntingdon, Indiana, Jefferson, Juniata, Lancaster, Lycoming, Mifflin, Perry, Snyder, Somerset, Warren, and Westmoreland. Below is a map showing the Disease Management Areas (DMAs) and Established Area (EA) as of the publication of this digest. More detailed and current maps of the DMAs and EA boundaries can be found at www.arcg.is/1G4TLr.
Because CWD sampling of deer and elk occurs year-round, this map may have changed due to additional positive detections and new areas may be included. For the most recent information, please visit www.arcg.is/1G4TLr.
Within Disease Management Areas (DMAs) and Established Areas (EAs) the following is prohibited:
Statewide the following is prohibited:
Statewide the following is allowed:
Hunters play a vital role in CWD management. The Game Commission gives hunters expanded opportunities to harvest deer in DMAs through CWD DMAP areas. The purpose of these units is to increase harvest and surveillance in areas located around new or high priority CWD detections. Successful hunters can submit the heads from harvested animals for free CWD testing to help assess the extent of the disease in these areas.
For the 2024-25 hunting season, the Pennsylvania Game Commission is offering DMAP permits for CWD DMAP areas. These permits allow hunters to take up to two additional antlerless deer. Permits will become available for purchase in August. Locations of current CWD DMAP areas can be found at www.arcg.is/1G4TLr.
The Game Commission offers free CWD testing to hunters who harvest a deer inside a DMA or EA. Hunters may submit their deer for testing by placing their deer head – double bagged and with harvest tag completed and firmly affixed to the ear – into any Game Commission-provided head collection bin. For antlered deer, hunters should remove the antlers and/or skull cap prior to submission. Antlers will not be returned if attached to a head submitted for CWD testing. Go to www.arcg.is/1G4TLr or call the CWD hotline at 1-833-INFOCWD for bin locations.
The Game Commission encourages hunters to check their test results online by using this QR code or going www.pgc.pa.gov/CWD. Click the “CWD Test Results and Surveillance Data” link under “Resources” and enter your hunting license CID number and date of birth. Hunters can also check their test results by calling the CWD hotline. Results take approximately two to three weeks and hunters who receive a positive test result will be notified by certified letter. Hunters who harvest a deer outside of a DMA or EA can get their deer tested through the Pennsylvania Animal Diagnostic Laboratory System for a fee. More information is available at www.padls.agriculture.pa.gov.
*The Game Commission conducts random CWD sampling at participating processors across the state, but using a processor that is enrolled in this program does NOT guarantee your deer will be tested. To guarantee a deer is tested for CWD, the head must be deposited into an agency head collection bin.
Hunters who hunt inside of a DMA or EA may dispose of highrisk parts with their commercial trash service if trash is deposited in a lined landfill. Parts disposed of in this way should be doubled bagged. In addition, hunters hunting inside of the EA can dispose of high-risk parts in dumpsters provided by the Game Commission. Locations of these dumpsters can be found at www.arcg.is/1G4TLr.
While not recommended, hunters hunting inside of a DMA or EA may leave all high-risk parts at the location of the kill site. It is recommended that all parts disposed of in this way be buried.
Cooperating processors work with the Game Commission to ensure all high-risk parts left with them are disposed of in the proper way to reduce the risk of disease spread from contaminated carcass parts. Locations of these cooperating processors can be found at www.arcg.is/1G4TLr.
For more information on CWD, visit the Game Commission’s CWD webpage by using the QR code or visiting www.arcg.is/1G4TLr. For questions, comments, and concerns use the CWD hotline at 1-833-INFOCWD (1-833-463-6293) or email us at infocwd@pa.gov.