Iowa DNR Warns the ‘Zombie Deer Disease’ is Expanding Across the State
Chronic Wasting Disease (CWD), a fatal neurological illness affecting whitetail deer, is causing growing concern in Iowa. Detected increasingly in central Iowa, far from its previous hotspots, and with a decade having passed since its initial appearance, experts fear an impending surge in its threat. The disease tends to progress slowly for the first six to ten years before experiencing exponential growth.
In a recent news release, Tyler Harms from the Iowa Department of Natural Resources (DNR) warned of a similar pattern in central Iowa, mirroring the rapid growth seen in northeast Iowa.
Last year, the DNR's surveillance program identified 96 CWD-infected deer—nearly double the previous year's count—mainly in northeast and southern Iowa. Alarmingly, cases have now appeared in central regions like Grundy, Jasper, and Marshall counties. The disease's expansion raises statewide concerns. The DNR, which has been conducting extensive testing and targeted hunts, reveals the prion's ability to surface almost anywhere. In just a years' time across the state, CWD numbers have risen 1%, from.9 in 21/22 to 1.9 in 22/23.
What is Chronic Wasting Disease and what does it do?
The prion, an abnormal protein, damages deer brains, leading to a prolonged decline. Affected deer may appear healthy, but as the disease progresses, they lose weight, display altered behavior, and experience impaired movement. The disease has caused the "Zombie Deer" phenomenon, where sickly and dead looking deer stumble around blindly and sometimes aggressively. CWD spreads through bodily fluids, feces, and contaminated environments, infecting deer through ingestion. Once infected the disease is always deadly to deer and other cervids.
Just last year the United States Department of Agriculture’s Animal and Plant Health Inspection Service, or APHIS, provided $9.4 million dollars to 27 states and 6 Tribes or Tribal organizations to further develop and implement Chronic Wasting Disease management and response activities in wild and farmed cervids (members of the deer/elk family). Iowa and Wisconsin both received this funding. The Wisconsin DNR received $323,388, with the Iowa DNR getting $247,702.
"In Wisconsin, where the disease was first discovered in 2002, one county’s male deer population is about 50% infected."
-Tyler Harms, Iowa Department of Natural Resources
Although CWD does not infect humans, the impact on deer populations and hunting industries is significant. Central Iowa's infection highlights the urgency for vigilance and control to curtail CWD's spread, protect deer populations, and safeguard the state's hunting economy.
How Can Hunters Help With CWD?
According to the Iowa DNR, hunters who harvest deer in counties where chronic wasting disease has been confirmed can avoid unintentionally spreading the disease to new areas by not moving carcasses out of those counties, and disposing of them at landfills when possible or burying them on the land where they were taken.
In addition, chronic wasting disease spreads from deer to deer through a misshapen protein in the saliva, feces, urine, and blood from an infected deer that can last in the environment for years, spreading the disease long after the source deer is dead. To help prevent the spread, hunters are encouraged to not set out mineral licks or bait that will congregate deer, thus potentially increasing disease transmission.