Portage County confirms chronic wasting disease on a deer farm
A deer farm in Portage County, located in central Wisconsin, has been placed under quarantine after a 3-year-old buck tested positive for chronic wasting disease (CWD). The confirmation came from the Wisconsin Department of Agriculture, Trade and Consumer Protection (DATCP) and was verified by the National Veterinary Services Laboratories in Ames, Iowa. The farm will remain quarantined as veterinarians from DATCP and the U.S. Department of Agriculture conduct a thorough epidemiologic investigation into how the disease arrived on the premises and whether other animals or environmental factors played a role.
Portage County has a history with CWD, with incidents involving both free-ranging and captive cervids previously identified in the area. The county sits in a region where several neighboring counties also report CWD-positive animals, underscoring the persistent challenge of controlling this fatal disease in wildlife and captive herds.
What is CWD and how does it spread?
CWD is a fatal neurodegenerative disease affecting cervids such as deer, elk, and moose. It is caused by misfolded infectious proteins known as prions. These prions spread through body fluids and can persist in the environment, making control efforts complex. CWD is categorized as a transmissible spongiform encephalopathy (TSE), a family of diseases that also includes scrapie in sheep, Creutzfeldt-Jakob disease in humans, and bovine spongiform encephalopathy (“mad cow” disease) in cattle.
While current evidence does not indicate that CWD poses a risk to humans, health authorities advise against consuming meat from infected or sick cervids and emphasize caution when handling carcasses. Hunters and handlers are urged to follow safety protocols to minimize exposure to infectious materials and environmental contamination.
Implications for the farm, wildlife, and public health
The immediate implication is a quarantine that restricts movement of animals and products from the affected farm until further testing and assessments are completed. The multi-agency epidemiologic investigation seeks to determine the source of the infection, assess the risk to other animals on adjacent properties, and implement measures to prevent further spread. The investigation may include testing other animals on the premises, examining feed and water sources, and evaluating fencing and biosecurity practices.
For wildlife management, the case highlights the ongoing need for surveillance and protection programs in wild cervid populations. Coordinated efforts between state agencies, veterinary laboratories, and wildlife professionals are essential to monitor the spread of CWD and to implement strategies such as targeted testing, habitat management, and hunter education to reduce transmission risk.
What residents and hunters should know
Residents and hunters in the region should remain vigilant and report any unusual deer behavior or carcasses to local wildlife authorities. Safe handling practices when field-dressing deer, using protective gloves, and properly disposing of potentially contaminated material are important steps in reducing exposure risk. Hunters who test positive for CWD in a harvested animal should follow state guidance regarding consumption and reporting.
Looking ahead
The DATCP and USDA will monitor the situation closely, with updates issued as the epidemiologic investigation progresses. While CWD remains a concern for both captive cervid facilities and wild populations in Wisconsin, coordinated surveillance, rapid reporting, and adherence to biosecurity measures are the cornerstone of efforts to protect animal health and prevent spillover into other herds and environments.
