|June 17, 2013|
It's not 'mad cow' disease, Canadian authorities say.
|The Fraser Health authority is trying to stamp out fears of a mad cow disease outbreak, saying three patients with suspected Creutzfeldt-Jakob disease did not get sick from eating contaminated beef. |
One person has died and two others remain gravely ill in hospital with the rare neurological disorder often linked to bovine spongiform encephalopathy, better known as mad cow disease.
A hospital worker leaked the information on Friday, sparking concerns mad cow disease had spread in the province, said Dr. Paul Van Buynder, chief medical health officer at Fraser Health.
"I think the really important thing to get out is that this is 'classic' Creutzfeldt-Jakob. It's a disease that happens for reasons we don't understand," he said.
"It's not 'variant' Creutzfeldt-Jakob, which is associated with food and mad cow disease and all the things people are worried about."
Over the last 12 months, the health authority has been investigating six possible cases, two in the same hospital at the same time. There are typically five cases per year in the province. Doctors were able to confirm one case using the brain tissue of the recently deceased patient.
The other two suspected cases remain in hospital and are very ill, Van Buynder said.
But a series of diagnostic tests like MRI and ECG scans and blood tests showed it is "highly unlikely" the three others have Creutzfeldt-Jakob disease after all, although only a post-mortem would give 100-per-cent confidence, Van Buynder said.
In Canada, according to the B.C. Ministry of Health, there are between 30 and 50 confirmed cases per year of Creutzfeldt-Jakob disease, which are only very rarely linked to mad cow disease, said provincial health officer Dr. Perry Kendall.
Only two people have ever been diagnosed with mad cow disease in Canada, in 2002 and 2011, neither from eating Canadian beef.
"One of the human forms can be contracted if you eat contaminated beef," Kendall said.
"Most cases are called classic, sporadic (Creutzfeldt-Jakob disease), which in 90 per cent of the cases you don't know why people get it because there is no obvious risk factor."
Eating beef in B.C. is just as safe as ever, Kendall said.
The recent suspected cases all involve older Canadians exhibiting symptoms like dementia or early-onset Alzheimer's.
Bovine spongiform encephalopathy is a fatal degenerative neurological disease found in cattle that can be transferred to humans after eating contaminated meat. It was first identified in Britain in 1986, leading to widespread herd culls and huge changes in animal feed guidelines. Over 230 people have died worldwide.
With Creutzfeldt-Jakob disease, patients fall ill, losing their memory and other cognitive functions, usually dying within six months. There is no known treatment or prevention.