What does chronic wasting disease look like?

Chronic wasting disease (CWD)

It is significant in prion disease. It affects in farmed animals and wild animals. It is prion disease of white-tailed deer, mule and randomly in moose. It was discovered in 1970 by E.S Williams. It is exotic disease. It is contagious. It is endemic in world. It was analyzed at Colorado Division of Wildlife Foothills Wildlife Research. It spreads due to shortage of food and stress. Mostly it has occurred in USA.

What does chronic wasting disease look like?
Chronic wasting disease (CWD)


It came from experimented infected animals. It causes gradually weight loss. It changes behavior such as isolation and depression in animals. Hypersalivation, odontoprisis, esophageal dilation, ataxia with head tumor, regurgitation, aspiration pneumonia and polyuria are symptoms. Environmental stress cause death. In central nervous system lesions are appeared in gray matter. Hypertrophy, neuronal degeneration and astrocytic hyperplasia can be appeared. Amyloid plaques are observed by hematoxylin-eosin staining of brain. Vacuoles surrounds the brain cells. Immunohistochemistry provides better result to observe spongiform. In brain, spinal cord, nerves, ganglia, endocrine tissues and lymph nodes CWD accumulate. Vagus nerve is affected extremely. Prions also start to grow in skeletal muscle. In saliva, blood, urine prions present.

Prions in Environment

CWD is captive. Horizontal transmission to wild herds are high. CWD also effect cervids of skeletal muscle. Fungi enzymes, heat, proteases, chemical disinfectants, UV radiations, soil inhabitants digesters and by mineral phases prion dispersed. In aquatic areas prion also travel to mineral and metal deposits. It is spread from infected animals through help of forage and water sources. In food, water and bedding prion can be observed. Cervids are present on apical skin layer. Soil contamination can cause CWD.


It is highly contagious disease. It can be transmitted from infected saliva, feces and urine. It was not identified that what exactly natural source of CWD. CWD is spontaneous disease of cervids. BSE is possible source of sheep scrapie. By intracerebral inoculation sheep scrapie prion spread disease to elk. At polymorphic codon diseased elk can be heterozygous or homozygous. Minimize transmission of CWD is in cattle. Wolves, coyotes and bears can get this disease.

CWD strains

In different animals and different incubation periods different CWD strains are present. Spongiform lesions variation is difficult to identify. It has been confirmed that there are two strains of CWD.


At the starting of this disease there are no symptoms that’s why it is difficult to identify. In later stages of this disease symptoms are severe. There is progressive weight loss, hypersalivation, ataxia and polydipsia in later stages. Immunohistochemistry, ELISA test are performed to detect CWD. Amplification methods are done to observe prions. Ultrasensitive immunoassays and antibodies are used to detect infection.


This disease is fatal. There are no vaccines and prophylactic treatment available.


It is impossible to control CWD. In future it is difficult to eradicate. It is needed to clean environment. Public awareness is necessary. And during handling the meat wear rubber gloves.

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