On Jan. 22, 2025, researchers have identified chronic wasting disease (CWD) prions in raw, cooked, and cured meat from an infected elk in Texas, confirming the presence of the infectious CWD-causing agents in muscle but concluding that the risk of transmission to humans through consumption is still unclear and requires continued vigilance.

Cooking temperatures are well known to be ineffective in disabling CWD prions, which are misfolded cervid (eg, deer, moose, elk) prions, leading to neurologic disease and death. The prions spread among cervids and through environmental contamination. There is no vaccine or treatment for CWD, which has been found in 35 U.S. states, Canada, Norway, Finland, Sweden, and South Korea.

The research team led by University of Texas Health Science Center used protein misfolding cyclic amplification (PMCA) and Western blot to test filets, jerky steak, hamburger, chili meat, sausage, ham, cutlets, and boneless steaks from a 5-year-old bull elk harvested in December 2020 on a Medina County high-fence hunting ranch. 

After meat processing, immunohistochemistry tests revealed CWD prions in the obex region of the animal’s brain, but the lymph nodes weren’t tested.

The first three PMCA rounds identified CWD prions in raw boneless steak, sausages and cutlets, and jerky, respectively. Grilling the meat to medium-well doneness substantially boosted PMCA detection of prions, and five samples of hamburger, chili meat, ham, cutlets, and boneless steak tested positive in a first PMCA round. 

A second PMCA round found prions in jerky, and a third identified prions in all grilled and boiled meats. Boiling different cuts of the same samples produced similar results, and the water used to boil the meat was also CWD-positive on PMCA.

Using PMCA to estimate the zoonotic properties of prions—their ability to spread from animals to people—in raw and cooked meats showed that none of the meat samples could induce conversion of normal human prion protein to an abnormal, infectious form characteristic of prion disease, which the researchers say suggests limited zoonotic potential. The study was published in Emerging Infectious Disease.