Page 4 - MDWFP CWD Response Plan
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disease with major efforts focused on containing the disease and monitoring its prevalence
                   within a defined area.

                   Response and support teams will be assembled with specific outlined responsibilities. The
                   MDWFP will rely on partnerships with private citizens and other governmental agencies to
                   manage CWD in the state.


                                                        Introduction

                   Overview of Chronic Wasting Disease

                   Chronic Wasting Disease (CWD) is a transmissible, fatal, neurological disease that affects
                   members of the Cervidae (deer) family. The agent for this disease is neither bacterial nor
                   viral, but is believed to be caused by a misfolded protein “prion” that replicates and infects
                   other normal proteins (Fryer and McLean 2011). This neurological disease is in the family of
                   infectious diseases knowns as transmissible spongiform encephalopathies (TSEs). Other
                   TSEs include bovine spongiform encephalopathy (BSE) in cattle, scrapie in sheep, feline
                   spongiform encephalopathy in cats, and Creutzfeldt-Jakob disease (CJD) and variant (vCJD)
                   in humans.

                   CWD is named for the symptoms caused by the disease which include: excessive salivation,
                   appetite loss, weight loss, and behavioral changes (Williams 2005). Diagnosis of the disease
                   cannot be based on clinical symptoms alone since other diseases can cause the animal to
                   exhibit similar symptoms. There is currently no USDA-approved, live-animal test for CWD.
                   The preferred test used to diagnose CWD is the immunohistochemistry (IHC) method, which
                   measures accumulations of CWD-associated prion protein in brain and lymph node tissues.
                   Incubation periods in naturally-exposed, free-ranging deer are difficult to determine, but
                   average incubation periods are thought to be two to four years but can vary greatly (Williams
                   2005). From the time clinical symptoms are identified, death occurs within several months
                   (Williams et al. 2002). Research on captive deer found that mule deer and white-tailed deer
                   infected with CWD died within 41 and 59 months, respectively (Miller and Wild 2004).

                   The United States Center for Disease Control and Prevention and the World Health
                   Organization have reviewed available scientific data and conclude that currently there is no
                   evidence that CWD can be transmitted to humans (Belay et al 2004, Campbell and
                   VerCauteren 2011).

                   CWD was first confirmed in mule deer at the Colorado Division of Wildlife captive wildlife
                   research facility in Fort Collins in 1967. The first documented case of CWD in a free-
                   ranging cervid was discovered in 1981 in a Colorado elk. The disease has since been
                   confirmed in Arkansas, Illinois, Iowa, Kansas, Maryland, Michigan, Minnesota, Missouri,
                   Montana, Nebraska, New Mexico, New York, North Dakota, Ohio, Oklahoma, Pennsylvania,
                   South Dakota, Texas, Utah, Virginia, West Virginia, Wisconsin, and Wyoming.
                   Additionally, the Canadian provinces of Alberta and Saskatchewan are CWD positive. In
                   October 2015, a CWD positive free-ranging elk was harvested near Pruitt, AR in Newton
                   County. As of August 2017 AR has confirmed 208 CWD positive white-tailed deer and 6




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