Waikato man cleared of vCJD

2.40pm

A Waikato man admitted to hospital with a suspected case of a fatal brain-wasting disease has been cleared after tests.

The Health Ministry's public health director Colin Tukuitonga told reporters tests in Melbourne had come back negative.

"The Ministry of Health has been advised today of the test results ruling out vCJD as a diagnosis," he said.

Tests on the man's tonsils returned negative, he said.

"Health authorities are now confident this diagnosis can be excluded and there are no risks to public health," he said.

A second test on the man's cerebral spinal fluid was "suggestive of sporadic CJD", Dr Tukuitonga said.

Sporadic CJD infects three or four people in New Zealand each year -- almost always aged 50-65.

The Health Ministry announced eight days ago it was awaiting results of tests on the 26-year-old farm worker to see if he had variant creutzfeldt-jakob disease (vCJD).

The disease vCJD is thought to be caused by eating meat or meat products from cattle infected with madcow disease (bovine spongiform encephalopathy, or BSE).

The New Zealand Food Safety Authority and the Ministry of Agriculture of Forestry (MAF) announced today the man had been cleared.

While the results might relieve concern from the farming sector, the man was still considered very ill in Waikato Hospital.

"This is an extremely difficult time for the family," Derek Belton, MAF director of animal biosecurity said in a statement.

"However, the exposure in this case has highlighted the enormous volume of evidence that New Zealand is BSE free, and the importance of the measures we have in place to maintain BSE freedom," Dr Belton said.

Food Safety Authority spokesman Stuart MacDiarmid said the scare could well be repeated in the future.

"We have to remind New Zealanders that although vCJD has been ruled out in this case, we believe that cases could well be seen in future," Dr MacDiarmid said in a statement.

"For several years we have recognised the risk of cases of vCJD in New Zealand because of exposure to risk material in foods imported prior to 1996 and because of the amount of overseas travel New Zealanders do. This case was a timely reminder to us all that it could happen here."

The health authorities wanted to provide a reassurance that New Zealand continued to be BSE free and there were extensive measures in place to protect the food supply from it.

There were other possible diagnoses for the man's illness, including "ordinary" CJD, alzheimer's or other brain diseases.

He remained in a stable condition in a general ward at Waikato Hospital this morning.

Paul Timmings, the man's neurologist, said earlier two samples from the man -- spinal fluid and a tonsil -- had been sent to Australia for testing in addition to other tests.

Results of the fluid were expected this week and the tonsil results next week.

The fluid test for vCJD is at best suggestive and the tonsil test has high rates of false positives and false negatives. Dr Timmings said the false negative rate was 25 to 30 per cent.

The Government revealed the man's illness on August 8 because it was under pressure from trade and agriculture sectors to dispel mistaken reports from Britain of a foot-and-mouth disease outbreak in New Zealand.

New Zealand has never had foot-and-mouth disease or BSE in its cattle.


- NZPA