Nebraskaland

58 Nebraskaland • November 2024 MIXED BAG North America's deer, elk and moose continue to face a silent killer. First identifi ed in Colorado in 1967, chronic wasting disease is now in Nebraska, 33 other states and four Canadian provinces. It has no cure or eff ective treatment. CWD is caused by prions — misfolded proteins that cause neighboring proteins to misfold. These prions accumulate in the brain and lead to erratic behavior, drastic weight loss and an emaciated appearance. Unlike the viral epizootic hemorrhagic disease that kills deer within days, CWD progresses slowly, said Todd Nordeen, big game disease and research program manager for Nebraska Game and Parks. It can take about two years before an infected animal will show symptoms. As its motor functions deteriorate, it also becomes more susceptible to predation, vehicle collisions and hunters. "We've gotten to some that are showing late- stage symptoms, but usually something else beats us to it," Nordeen said. Believed to be spread among susceptible species by body fl uids, prions can persist in soil and vegetation for decades, complicating eff orts to contain it. "It's a very diffi cult disease to deal with," Nordeen said. "It's so hard to destroy. It's not eliminated by fi re or freezing." Proteins, which are not formally living things, are the building blocks for tissues, muscles and organs. When misfolded, as prions, they wreak havoc on an organism's mental function. Other prion diseases include Creutzfeldt- Jakob disease in humans and bovine spongiform encephalopathy, known as mad cow disease. Thankfully, no evidence suggests CWD poses a direct threat to humans. The Centers for Disease Control and Prevention encourages caution, however. People should wear gloves and a mask when handling big game species, especially the brain and spinal cord where prions accumulate the most. To limit the diseases' spread, carcasses should be double bagged and taken to a licensed landfi ll. "Proper disposal is especially important with CWD," Nordeen said. Knowing what they are up against, researchers and wildlife managers are doing their part to monitor and control the disease. In February, 59 Panhandle mule deer were captured and equipped with tracking collars as part of the USDA National Wildlife Research Center's interstate eff orts to study chronic wasting disease. Information obtained during the captures, including blood and tissue samples, gives insights into the species health. Each year, lymph nodes also are collected in fi ve of 18 deer units in a statistical-based approach to discovering new areas where the disease is present. Before the 2024 deer season, CWD had been detected in free-ranging deer and elk in 58 of 93 counties — all of the Panhandle and southwestern region, with other counties ranging to the eastern border. Since 1997, Game and Parks has tested more than 57,000 deer and over 400 elk, with 1,269 deer and 19 elk testing positive. The rate of positive animals has exceeded 30 percent in some states, but is not that high in most areas in Nebraska. Some eastern units are 5 percent or less. But at their last testing in 2022, the Plains, Frenchman and Pine Ridge units in western Nebraska each tested at about 30 percent. Some states are implementing regulations to prevent the movement of potentially infected carcasses, while others are exploring experimental treatments and vaccines. In the meantime, in Nebraska, biologists are furthering their research, understanding and education on the disease in the hopes of fi nding solutions for the future. They are asking the public to report suspected diseased animals to Game and Parks — and to spread awareness of the disease. Learn more about CWD at OutdoorNebraska.gov; search for "CWD." CWD NOT GOING AWAY SOON By Justin Haag Workers collect blood and tissue samples from a mule deer in the Wildcat Hills while equipping it with a tag and tracking collar. The capture eff ort in February was part of a multi-state eff ort to study Chronic Wasting Disease. JUSTIN HAAG, NEBRASKALAND

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