Scientists and state livestock officials remain skeptical that a hunter’s death in Colorado from a rare brain disease is related to Chronic Wasting Disease. Still, the link has not been ruled out.
Otto Berns, formerly of Thornton, Colo., was an avid hunter who ate a lot of venison. He first noticed signs of memory loss in early May, and after a biopsy in June, was diagnosed with Creutzfeldt-Jakob Disease (CJD). He died July 10 at the age of 63.
Berns’ death has raised concerns that Chronic Wasting Disease (CWD), an ailment similar to the disease that killed Berns but is endemic to deer and elk, has spread across the species barrier.
Berns hunted in the “Colorado Endemic Area,” so named because of the high incidence of CWD. Berns’ family suspects that he contracted the disease from eating tainted game.
Creutzfeldt-Jakob Disease occurs most often in people ages 50 to 75. It has an onset time of 15 months to 30 years. The disease is characterized by a rapid deterioration of the brain and the breakdown of mental functions. While it only affects about one person in 1 million, there is no known cure, and is always fatal.
Chronic Wasting Disease has not yet been linked to CJD, but its cousin, Mad Cow Disease, has. A new variant of the human ailment is thought to result from consumption of beef tainted with Mad Cow Disease, and has affected about 125 people, according to the U.S. Centers for Disease Control.
Mark Mattix, Montana’s veterinary pathologist, is skeptical of the connection.
“To date, there has not been any cross-species transmission,” he says. “And it isn’t even certain that the new variant of Mad Cow Disease crosses species.”
Mattix is skeptical of any connection between Berns’ death and CWD, noting that there is so much about the disease that is unknown.
For example, scientists aren’t even sure what causes the disease in elk and deer, having narrowed down its cause to three likely suspects. These are a mutant protein, an unconventional virus, or a virino, an incomplete virus too small for the immune system to notice. Scientists also aren’t sure how the disease spreads, whether it’s animal-to-animal, blood-borne, or both.
Nevertheless, Montana has taken precautions against the spread of CWD. While only one elk herd was infected in Philipsburg, another herd came in contact with them. As a result, both herds were destroyed, says Karen Cooper of the Montana Department of Livestock.
Killing elk and deer infected with the disease may not be enough to stop the spread of the disease. One of the problems with CWD is that it is very difficult to eradicate, says Dr. Minnot Pruyn, a local veterinarian.
“Just because you’ve killed the deer and charbroiled it doesn’t mean you’ve killed the disease,” says Pruyn.
While Pruyn shares some of Mattix’ skepticism, he hasn’t ruled out the possibility that the disease that strikes deer and elk might be linked to its human counterpart.
“There is a possibility that it has occurred,” he says, “but it isn’t very likely.”