One case of rare brain disease confirmed in B.C.

One case of a rare, degenerative brain disease has been confirmed in British Columbia's Fraser Valley, and a health official says two other cases are now suspected.

However Paul Van Buynder, chief medical officer for the Fraser Health authority, said late Friday that even if the two suspected cases end up being Creutzfeldt-Jakob disease it's not "drastically unusual."

The confirmed case of Creutzfeldt-Jakob disease, or CJD, was a resident in a long-term care home who died a year ago, Van Buynder said.

He said the two other patients suspected of having Creutzfeldt-Jakob disease are currently hospitalized. None of the patients are related; all lived in different towns.

The findings stem from a review officials conducted after they initially believed there were six CJD cases in the Fraser Valley, east of Vancouver, over the past year.

Buynder said it's "highly unlikely" that the remaining three cases will be confirmed as CJD.

Cases are only confirmed after a sample of brain tissue, typically taken from the patient post-mortem, is tested at a national laboratory, he said.

Before that happens, doctors make an initial diagnosis based on MRI images, blood tested for specific proteins and an electroencephalogram, a test that measures the brain's activity.

Only 30 to 50 cases are reported annually in Canada, and five of those cases are expected to occur in British Columbia, he said.

"I think the public really need to know that this is probably one or two more than I expect, but it's not drastically unusual," said Van Buynder.

"It's not mad cow disease. It has nothing to do with the food chain. Neither the public nor anybody in our hospitals should be worried that they're about to get this nasty disease."

Provincial health officer Dr. Perry Kendall said CJD causes the rapid onset of dementia, leading to a coma usually within a six-month time frame, because agents known as preons destroy the brain.

One strain has been linked with mad cow disease, but Van Buynder said more than 90 percent of the cases are sporadic and health officials don't know its cause, and they have no treatment or cure.

"It's a tragic disease that is rapidly progressing," he said. "It's a degenerative disease of the brain and usually within six months they've passed away. It's a tragic disease for families, and we just really don't understand it."

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