A deadly disease that’s threatening deer herds across the country is prompting South Carolina wildlife officials to reconsider which products hunters are allowed to use to lure trophy bucks.

The state Department of Natural Resources wants to introduce a regulation that would ban hunters from using scent lures that contain natural deer urine, according to Charles Ruth, a certified wildlife biologist and big game program coordinator with the wildlife agency.

“It would take about a year for us to file the regulation and go through the legislative process, but we’d like to see a ban on natural urine products by the 2019 deer hunting season,” Ruth told the Greenville Journal during a recent phone interview.

Many hunters use buck and doe urines to lure deer to their location or cover their scent, but the foul-smelling liquid is thought to contribute to the spread of chronic wasting disease, according to Ruth.

Chronic wasting disease is a contagious, neurological illness affecting deer, elk, and moose populations throughout North America, according to Ruth. That includes the white-tailed deer, a popular game species in South Carolina. Greenville County hunters alone harvested more than 3,000 white-tailed deer in 2017.

“We haven’t detected signs of chronic wasting disease in South Carolina yet, but we don’t want to look back several years from now and wonder if we did everything possible to prevent it,” Ruth said.

Since it was first documented in a captive mule deer in Colorado about 35 years ago, CWD has slowly spread to more than two dozen states and a number of Canadian provinces, according to SCDNR.

Ruth said the disease, which has no treatment or cure, is caused by deformed proteins called prions that replicate upon ingestion and attack the animal’s central nervous system, ultimately killing it.

“The incubation period for chronic wasting disease can range from a year to five years,” he said. “But if a deer contracts the disease, it’s going to eventually die. There’s no question about it.”

Scientists believe CWD prions likely spread from deer to deer through feces, saliva, blood, or urine, either through direct contact or indirectly through environmental contamination of soil, food, or water, according to Ruth. Once a deer contracts the disease and dies, its tissues become vectors. The prions can only be destroyed by burying them in a landfill or through incineration.

While there has never been a documented case of a human contracting the disease, the Centers for Disease Control and Prevention recommends that people do not consume meat from an infected animal.

Natural scent lures pose a risk to South Carolina’s deer population, because they are often produced by facilities that collect urine over a grate system, which doesn’t prevent contamination from feces or saliva, according to Ruth.

Collection facilities also have no way of knowing whether or not their deer are disease-free, because there is no certified live-animal test for CWD, nor is there a way to test urine for prions once it’s been collected, according to Ruth. These facilities also generally don’t treat their urine-based products with chemicals or heat to kill the infectious proteins, because these treatments would secondarily destroy the desired scent characteristics.

Several states, including Alaska, Arizona, Virginia, and Vermont, have enacted outright bans on urine-based attractants, while others have drafted regional bans and/or rewrote rules to allow only synthetic lures. These bans, however, have been met with opposition from some hunters — who dribble the foul-smelling fluid on foliage near their tree stands — and manufacturers, who market products like “Cold Blue” and “Buck Bomb.”

Ralph Brendle, owner and president of River Bend Sportsman’s Resort in Spartanburg County, said the proposed regulation to ban urine-based attractants in South Carolina wouldn’t likely impact his business. “We don’t use scent lures of any kind. We just hunt them naturally in the woods,” he said. “The only thing we do is set out some bait every now and then.”

Brian Sullivan, co-owner and manager of Toney Creek Hunting Plantation in Anderson County, said his company currently uses urine-based attractants for guided deer hunts but won’t likely seek out an alternative if South Carolina enacts the ban. “Synthetic lure doesn’t work nearly as good,” he said. “I’d just prefer not use it.”

Ruth said the proposed regulation to ban urine-based lures in South Carolina would need to be passed by the General Assembly and signed into law by the governor before it could be enforced. If approved, it would become one of many regulations instituted by the wildlife agency over the years to combat the spread of CWD.

In an effort to help prevent the disease from entering South Carolina, SCDNR has banned the commercial transport of deer and other related species, such as elk and moose, since many cases of CWD have been linked to captive animals, according to Ruth.

The agency also continues to maintain regulations restricting the importation of whole carcasses or parts containing nervous system tissue from deer and elk harvested in the U.S. states and Canadian provinces where CWD has been documented, according to Ruth. If hunters dispose of these carcass parts in South Carolina, the disease agent could potentially infect deer in that area.

Ruth said South Carolina is far from any state where the disease has been diagnosed, but SCDNR has tested more than 6,000 deer from all 46 counties since 2002 and developed a response plan that’s designed to contain the spread of CWD should an outbreak occur.

Current research shows that CWD outbreaks can lead to significant declines in deer populations over time. In Wisconsin, for instance, the prevalence of the disease among adult male deer — those 2 ½ or older — has seen an annual growth rate of 23 percent since it was discovered in 2002.

John Quinn, an associate professor of biology at Furman University, said scientific understanding of the ecology and transmission of CWD in free-ranging wildlife is limited, but a major decline in South Carolina’s white-tailed deer population due to such a fatal disease would likely have ecological consequences.

The white-tailed deer is considered to be a keystone species, one whose very activities have an immediate effect on both the landscape and the natural habitats of other animals in the wild, according to Quinn.

White-tailed deer not only serve as prey for coyotes and other predators, but their feeding habits and preferences can affect the variety, quality, and structure of plants in a habitat, Quinn explained. While chronic browsing can kill or hinder the growth of preferred plants in an ecosystem, deer avoidance of non-native, invasive plant species can cause them to become more prevalent and spread faster.

“A loss of deer populations is going to change forest understory,” Quinn said.

Quinn said a decline in South Carolina’s white-tailed deer population would also likely lead to fewer hunters, which in turn would mean less dollars for SCDNR, which collects a large portion of its funding from hunting-license sales and federal excise taxes on firearms, ammunition, and other hunting equipment.

Deer hunting generates more than $200 million annually for the state’s economy, according to Ruth. South Carolina sells more than 700,000 recreational licenses each year to residents and out-of-state hunters and fishermen.

Recreational and commercial hunting licenses can be purchased online at dnrlicensing.sc.gov. Deer hunting on private lands in Game Zones 1 and 2, both of which include parts of Greenville County, runs through Jan. 1, 2019.

For more information, visit www.dnr.sc.gov.