January 23, 2003
Purdue, state test deer and elk for fatal disease
WEST LAFAYETTE, Ind. ‹ Purdue University and the state of Indiana have joined a
federal effort to prevent spread of chronic wasting disease, a fatal illness
that has been detected in wild and domestic deer and elk in 11 states, not
month, pathologists at the Indiana Animal Disease Diagnostic Laboratories
(ADDL), based on the Purdue campus, began using a new machine to test tissue
samples to determine whether deer or elk are infected with the disease. While
no cases of chronic wasting disease (CWD) have been found in Indiana, seven cases
were discovered since last November in northern Illinois. Wisconsin found the
first cases east of the Mississippi River in February 2002.
have signed an agreement with the federal government to test samples from deer
from Indiana and any other state that needs a diagnosis on possible CWD
cases," said Randy White, Purdue associate professor and a veterinary
pathologist with ADDL. "In Indiana, we need to be concerned because
animals don't respect state boundary lines and CWD is very close to us in Illinois
wasting disease is a transmissible spongiform encephalopathy found only in
cervids, the animal family that includes deer, elk, caribou and moose. It is
similar to bovine spongiform encephalopathy (BSE), commonly referred to as mad
cow disease. Though BSE has been linked to human illness in Great Britain,
scientists so far have found no evidence that meat from CWD-infected animals
can infect people, pets or other types of livestock.
researchers don't yet know the origin of the illness or how it's transmitted,
according to the U.S. Department of Agriculture's Animal and Plant Health
Inspection Service (APHIS). The disease is believed to be caused by an abnormal
type of protein called a prion (pree-on) that attacks the central nervous
system, including the brain, killing cells. This eventually creates holes in
the brain that give it a spongelike appearance.
we have nothing to show that eating CWD-infected deer and elk is harmful to
people, we can't say that it's okay or it's not okay to eat the meat,"
and two laboratory technicians recently trained at the USDA National Veterinary
Services Laboratory in Ames, Iowa, in the use of an automated and computerized
CWD diagnostic machine. The Purdue lab now has the same type of equipment used
by the national lab to test for chronic wasting disease. CWD was first
recognized in 1967 as a clinical wasting disease in mule deer at a federal
wildlife research facility in northern Colorado. It was identified as a
transmissible spongiform encephalopathy in 1978.
the mid-1980s, free-ranging deer and elk in adjacent areas of Colorado and
Wyoming were diagnosed with the deadly illness, according to APHIS. Since that
time, the national lab has handled all testing of suspected cases of chronic
said that Purdue, along with other laboratories in Illinois, Minnesota,
Michigan, Ohio, Texas and Arkansas, is now running tests for the disease. He
said he expects that the ADDL at Purdue will receive samples from surrounding
states and may receive some from national laboratory, so that diagnosis is
diagnostic process takes six to seven hours. First tissue samples from the
middle of the brain stem, called the obex, and from lymph nodes, are put on a
slide and loaded into a machine called a decloaker. This machine will expose
any prion antigens.
the slide is put into the staining machine, which can hold 20 slides, where a
dye containing an antibody is placed on the tissue. Antibodies are molecules
that detect a foreign disease-causing substance by binding to the antigens. If
abnormal prions are present, that area of tissue will turn bright red. A
pathologist must look at the tissues through a microscope to determine if
abnormal prions are present.
State Board of Animal Health, the USDA and the Indiana Department of Natural
Resources have instituted good programs to prevent the spread of CWD,"
White said. "People handling or eating deer and elk should take
precautions, because many things about this disease are still unknown."
seeing a deer that appears ill should call the local Indiana Department of
Natural Resources Fish and Wildlife Division office, which will handle the
initial investigation. The symptoms of the disease include listlessness,
staggering, emaciation, blank facial expression, excessive salivation, grinding
of teeth, and increased drinking and urination.
to APHIS, chronic wasting disease has been found in wild and farmed deer and
elk in South Dakota, Wyoming, New Mexico, Nebraska, Colorado, Oklahoma, Kansas,
Minnesota, Montana, Wisconsin and Illinois. The affected animals have been
Rocky Mountain elk, mule deer, white-tailed deer and black-tailed deer. Indiana
has a ban on imports of cervids that runs through May 1.
National Wildlife Federation estimates that the rate of infection in areas
where prion-diseased cervids have been found is approximately 1 percent in wild
elk, 5 percent in wild mule deer and 10 percent to 12 percent in wild
have been run placing domestic cattle, sheep and goats in research wildlife
facilities that housed CWD-infected deer and elk. None of the domestic animals
contracted the disease, according to the Animal and Plant Health Inspection
no human cases of CWD have been found, experts offer the following advice:
Don't eat the eyes, brain, spinal cord, spleen, tonsils or lymph nodes of any
deer or elk.
Don't eat any deer that appears sick.
Wear rubber or latex gloves when dressing carcasses.
Remove all meat from bones before cooking and eating.
Clean all equipment with a solution of half chlorine bleach and half water.
NOTE TO JOURNALISTS: A publication-quality photograph of Randy White is available at ftp://ftp.purdue.edu/pub/uns/white.wasting.jpeg.
Susan A. Steeves, (765) 496-7481, ssteeves@ purdue.edu
Randy White, (765) 494-7456, email@example.com
Related Web sites:
University Department of Veterinary Pathobiology:
Board of Animal Health: http://www.IN.gov/boah/
CWD Information Site: http://www.deerhealth.in.gov
Department of Natural Resources, CWD: http://www.in.gov/dnr/deerhealth/cwd.htm
Animal Plant Health Inspection Service: http://www.aphis.usda.gov
University veterinary pathologist Randy White operates new equipment that will
diagnose chronic wasting disease in deer and elk at the Animal Disease
Diagnostic Laboratory (ADDL). The state lab is now part of a federal program to
identify and prevent the spread of the disease, which is fatal to infected
animals. (Agricultural Communication photo/Tom Campbell)
publication-quality photograph is available at
Purdue News Service: (765) 494-2096; firstname.lastname@example.org
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