May 31, 2002 Capital Times (Madison, WI) by Anita WeierNo current test for chronic wasting disease can guarantee that venison is safe to eat, according to the head of pathology at the National Veterinary Services Laboratories in Ames, Iowa.
Hunters expecting to hunt and safely eat tested meat should know that disease surveillance tests are not food safety tests, Dr. Mark Hall said Thursday.
"Most of you will be angry with me," Hall told people gathered at the Department of Natural Resources headquarters who are considering developing private laboratories to test white-tailed deer in Wisconsin for the fatal nervous system disease.
Hall's laboratory does most CWD testing nationally and subcontracts with state laboratories for the rest. "No test is valid yet for white-tail," Hall said. "We already know we miss about 30 percent with brain tests. If we go the next step and say use lymphoids, it is still not 100 percent. We still don't have sufficient data to say the meat is absolutely safe to the hunter."
He stressed there has been no direct connection between CWD and Creutzfeldt-Jakob disease in humans, which has been connected with the mad cow version of prion disease in Europe.
Nevertheless, Hall said, deer from an infected area should not be eaten -- regardless.
"If you give someone a test result, who will say I guarantee it is 100 percent safe? To provide other than some misguided confidence, it is not a good idea to test all those animals. From a federal perspective, that is not the current thinking. We cannot assist you in food safety testing."
Hall said it would make much more sense for the state Department of Natural Resources to concentrate on killing the deer where the disease has been found in Dane, Iowa and Sauk counties and reducing the number of deer in nearby areas.
"If you can truly eradicate the disease instead of spending all that money on testing that may or may not be valid, the use of resources may be better to guarantee an area is safe," Hall said.
"A food safety claim is outside the jurisdiction of the USDA. We detect animal disease - not whether an individual animal is safe to eat."
He also warned that it is essential to have qualified labs doing testing, because tests that give false negatives would be a terrible problem. USDA's plan is to meet all testing demands of captive and targeted populations through federal and state labs.
"Other labs will be allowed to run tests, but our thrust will be to have state labs running them," he said. "We are building a lab system now."
"Is there any law that says private individuals can't talk to companies for testing regardless of federal approval?" asked Dr. Phil Bochsler of the Wisconsin Veterinary Diagnostics Laboratory.
Hall said that no federal law prohibits such testing. But the federal government issues permits to receive control samples from diseased animals only if the labs have passed inspection as Biosafety 2 labs.
Trygve Solberg, chairman of the Natural Resources Board, said that testing must be in place before the hunting season, because hunters will demand it.
"Testing is absolutely on top. People want to know if they can take it home and eat it. We want to see something done. Some people have said they are not goingto hunt," Solberg said.
"My concern is the confidence of the public in deer hunting and being able to continue to eat the meat and continue to hunt," board member Herb Behnke added. "We are looking at one-third saying I don't know if I'll hunt again.
"Do they need proof-positive? I don't need to know 30 percent chance of error. Are we looking at satisfying the need or going through a regulation process of two to four years instead? We can't afford to have 300,000 or 400,000 hunters not in the field."
Butch Johnson, one of three Hayward men hoping to develop a private laboratory to test for CWD, was equally impatient.
Johnson said he has been unable to get answers on how to proceed or which government agency is in charge.
"Where do we go from here and who will provide the information? If we have to partner with the Veterinary Diagnostics Lab, tell us. I have to know if I should spend $650,000 to buy equipment," Johnson said.
"I find it sad we are not talking about how we can collect brain and lymph at deer registration tables. We're not being aggressive enough."