Chronic wasting disease: how to spot and report the disease

Chronic wasting disease (CWD) is a highly contagious and fatal disease that affects most wild and farmed deer species including: red deer, roe deer, reindeer, North American moose (known as elk in Europe), white tailed deer (indigenous to North America), fallow deer, sika, Chinese water deer and muntjac.

Humans aren’t affected, neither are animal products nor meat such as venison.

Clinical signs

In most cases of CWD there is a general change in behaviour and loss of weight over time, particularly in the later stages of the disease.  Deer may show a number of different clinical signs over several weeks.  The disease is progressive and fatal.  Deer may take 18 to 24 months to show clinical signs after becoming infected and will become more infectious to other deer as the incubation progresses.

Changes in behaviour

You may see in infected deer:

• separation from other animals in the herd
• depression or blank facial expression
• lowering of the head
• difficulty in swallowing
• increased thirst and urination
• drooling
• pneumonia
• less interest in hay but continue to eat grain
• teeth grinding
• nervousness and excitement

Changes in posture and movement

You may see in infected deer:

• stumbling and incoordination
• listless and dull
• repetitive walking in set patterns
• tremor
• paralysis

 

How chronic wasting disease is spread

Contaminated clothing and equipment

Countryside users bringing in contaminated clothing and equipment could transmit CWD.

Hunters or stalkers who have hunted in parts of North America where CWD is present might transmit CWD in the UK.

CWD is highly infectious and very resistant to weather conditions and traditional disinfectants so it can remain in the environment for a long time. CWD can stick to soil particles for up to 10 years.

The only way to rapidly inactivate CWD’s infectious agent is to soak clothes or equipment in a solution of bleach that has 20,000 parts per million of active chlorine, or 2 molar sodium hydroxide solution, for one hour.

This treatment will damage or destroy most clothing, footwear and hunting equipment.

Deer urine lures

Hunters shouldn’t use or trade deer urine lures because they may contain infected urine which can transmit CWD. You can use synthetic lures.

Importing unprocessed deer urine into the EU is banned.

Human health implications

There are no human health implications because the disease is not zoonotic.

How to control the disease

If you report suspicion of CWD, APHA vets will investigate.

They may decide to keep your animal under observation to decide whether or not it’s a TSE suspect. The vet will restrict the movement of the animal from the farm and will visit the animal during the observation period.

If the vet decides that your animal is a TSE suspect, the vet will restrict the movement of animal and issue a notice of intention to kill. After death, brain samples will be sent for post-mortem laboratory examination.

Feed controls

You must not feed animal protein to ruminants, including deer, or processed animal protein to farmed deer, although there are exceptions. As CWD is a TSE disease you must follow TSE regulations and feed controls.

Biosecurity

You can help prevent the disease by practising strict biosecurity on your premises.