TESTING FOR CHRONIC WASTING DISEASE IN EARLY STAGES
Several presumptive positives detected, CWD possibly found in new counties
PRATT – Testing for chronic wasting disease (CWD) in samples collected from deer taken during the 2009 season is only about one-third complete, but the Kansas Department of Wildlife and Parks (KDWP) reports that six samples have shown presumptive positive. All collected samples are tested at the K-State Veterinary Diagnostic Laboratory, and any that test positive for CWD are considered “presumptive positive” and then sent to the National Veterinary Services Laboratory in Ames, Iowa for further testing and confirmation. Confirmation has not been received on these presumptive positives, but it’s possible that deer with CWD were taken in two Kansas counties where the disease has not been found before.
This year, presumptive positive test results have been found in samples from two deer taken in Decatur County, one taken in Rawlins County, one taken in Graham County, one taken in Sheridan County and one taken in Thomas County. CWD had not been detected in deer from Thomas or Graham counties previously. However, both counties are adjacent to counties where CWD had been detected in recent years.
KDWP has collected several thousand samples each year since 1996, and
CWD in wild deer was first detected in Cheyenne County in 2005. Three infected deer were taken from Decatur County in 2007 and 10 tested positive in 2008, from Decatur, Rawlins and Sheridan counties. This year, about 2,300 samples will be collected, with emphasis in northwest Kansas.
CWD is a member of the group of diseases called transmissible spongiform
encephalopathies (TSEs). Other diseases in this group include scrapie in sheep and goats, bovine spongiform encephalopathy (BSE or Mad Cow Disease) in cattle, and Cruetzfeldt-Jacob disease in people. CWD is a progressive, fatal disease that results in small holes developing in the brain, giving it a sponge-like appearance under the microscope. An animal may carry the disease without outward indication but in the later stages, signs may include behavioral changes such as decreased interactions with other animals, listlessness, lowering of the head, weight loss, repetitive walking in set patterns, and a lack of response to humans.
Currently there is no vaccine or other biological method that prevents the spread of CWD. There is no evidence that CWD poses a risk to humans or livestock, but precautions are advised. Hunters are advised not to eat meat from animals known to be infected and common sense precautions are advised when field dressing and processing meat from animals taken in areas where CWD is found. More information on CWD can be found on KDWP’s website, www.kdwp.state.ks.us or at the Chronic Wasting Disease Alliance website, www.cwd-info.org