NEW YORK/SAN FRANCISCO - Family and friends of American victims of Creutzfeldt-Jakob Disease, the fatal brain disorder sometimes linked to mad cow disease, on Friday questioned whether the wasting illness that killed their loved ones was actually due to eating contaminated U.S. beef.

After federal authorities said on Tuesday that a cow in Washington state was found to have mad cow disease, public health experts have been calling for a review of the U.S. Agriculture Department's screening procedures for cattle.

But some victim's families have gone further, saying that the human form of the disease may have already hit the United States and that the government has been lax in its testing possible links and enforcing safety standards.

"The most frustrating part of this disease is that there are no answers," said Chris Turnley, whose brother Peter Putnam, who grew up in Washington state, died of the disease last October at age 35. "They need to figure out the cause but also start figuring out treatments."

So far, none of the roughly 300 cases of Creutzfeldt-Jakob Disease diagnosed in the United States each year has been linked to U.S.-produced beef, said Pierluigi Gambetti, director of the National Prion Disease Pathology Surveillance Center at Case Western University.

But Dr. Michael Greger, a doctor in Scarsdale, New York, and coordinator for Organic Consumers Association, said it would be wrong to take comfort from that statistic. The disease has a long incubation period and few dementia-related deaths in the United States are investigated.

"There have been no confirmed cases, but just as there weren't any confirmed cases of mad cow disease, it is a function of how hard one looks for it," Greger said.

The variant of the illness linked to mad cow disease was first reported in Britain, where about 150 people have died and where mad cow disease was first identified in 1986.

The disease is marked by sudden and escalating neurological and muscular symptoms, including confusion, depression, behavioral changes and impaired vision and coordination.

Creutzfeldt-Jakob Disease occurs spontaneously at a rate of about one case per 1 million people. It is incurable and always fatal. A related illness, known as new variant CJD, has been linked in Europe to eating meat from cattle infected with mad cow disease.

'MYSTERY' ILLNESS

Patricia Ewanitz of Port Jefferson Station, New York, says she wonders about the death of her 58-year-old husband six years ago, diagnosed as Creutzfeld-Jakob.

"This didn't have to happen," said Ewanitz, co-founder of the CJD Voice support group. "We've been warning them (government agencies) that every cow that goes into the food chain should be tested."

In Kansas, 62-year-old Linda Foulke died of the disease last Sunday, and a specialist at the Wesley Medical Center in Wichita confirmed the diagnosis of Creutzfeldt-Jakob, the Wichita Eagle reported on Friday.

Bill Patton, Foulke's son-in-law, said doctors told the family the type of Creutzfeldt-Jakob disease Foulke contracted was different from the type tied to mad cow disease. But Patton was quoted as saying the family was worried there might be a connection.

Wesley Medical Center spokeswoman Cheryle Olsen said she would not comment on the case other than to say the family was likely too grief-stricken to understand the situation clearly.

Meanwhile in Putnam's case, his family says his death is a mystery and they are awaiting word from a British laboratory on a brain biopsy test. He first showed symptoms of the disease while living in Alaska.

Additional reporting by Jim Christie in San Francisco, Carey Gillam in Kansas City and Toni Clarke in New York

Copyright 2003 Reuters Ltd

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