BY KAREN SHIDELER

The Wichita Eagle

Health officials believe a Kansas man has died of Creutzfeldt-Jakob disease, a rare disease that affects the central nervous system and turns brain tissue spongy.

One variation of the disease is the so-called mad cow disease, but the human form of that has never been seen in the United States in someone who hadn't had exposure elsewhere.

Because the incubation period for the disease is years or even decades, health officials don't know how or when the Kansas man got the disease, nor what its source may have been.

They won't know for several weeks, until testing is complete, which form of the disease he had.

The man died Friday at Wesley Medical Center, where he had been a patient since December. His name was not released, but he was a 53-year-old from the Colby area.

The diagnosis at this time is Creutzfeldt-Jakob disease, or CJD, said Wesley spokesman Paul Petitte. The only way to confirm CJD is through testing of brain tissue, which will be done through the National Prion Disease Pathology Surveillance Center.

Kansas has an average of three CJD cases a year, according to Joe Blubaugh, spokesman for the state Department of Health and Environment.

Nationwide, according to the Centers for Disease Control and Prevention, one to two people per million have a spontaneous case of CJD each year. On average, 250 to 300 cases of CJD are reported annually.

In addition to the spontaneous cases, a certain form of CJD can come from consumption of beef that has been infected with mad cow disease, as happened in Great Britain in the mid-1990s. The United States and other countries implemented various measures in response, to prevent the disease and better track infected cattle.

CJD also can come from blood transfusions, and it can be hereditary in very rare cases.

Richard Liepins, who was the attending physician in the local case, said, "We have no idea of how he possibly contracted this."

The man worked in a meatpacking plant "quite a few years ago" and was also an elk hunter, Liepins said, though there's no way to say whether either of those contributed to his disease.

Chronic wasting disease, found in some deer and elk, is another form of spongiform encephalopathy. It can be spread from animal to animal, but so far there's no strong evidence of its transmission to humans.

The CDC said studies are under way to see whether people exposed to the meat of sick deer and elk are at increased risk for CJD, but because of the long incubation period that won't be known for years. Hunters and others are advised to avoid meat from animals that seem sick or test positive for chronic wasting disease.

The disease is rare enough that Liepins and some of the other doctors who worked on the case had never seen it before. Tom Moore, an infectious disease specialist in Wichita, said he has seen about three cases over the past decade.

When the man first became ill doctors suspected a brain tumor, Liepins said, because of his neurological symptoms. Such symptoms include personality changes, other mental changes and dementia, which are also among the symptoms of CJD.

Liepins said he wouldn't speculate on the most likely cause of the man's disease, but he said there is no reason for concern among the general public.

"It's a rare disease that people can contract at any time, but it's rare -- it's very rare," he said.

Reach Karen Shideler at 316-268-6674 or kshideler@wichitaeagle.com.