Chronic Wasting Disease (CWD) – how to spot and report the disease
How to spot CWD and what to do if you suspect it and measures to prevent its spread.
CWD is a highly contagious and fatal disease that affects most wild and farmed deer species including:
Humans aren’t affected, nor are animal products or meat such as venison.
There have been no outbreaks in the UK but in 2016 it was diagnosed in wild deer in Norway, the first cases of CWD in Europe. The disease has also killed wild and farmed deer in North America.
The latest Qualitative Risk Assessment on the risk of a cervid transmissible spongiform encephalopathy (TSE) being introduced from Norway into Great Britain concludes that the public health risk of CWD isn’t known. Current assessments suggest the risk is very low.
CWD is a notifiable disease – if you suspect it you must tell the Animal and Plant Health Agency (APHA) immediately. Failure to do so is an offence.
How to spot CWD
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
- 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
Current Situation in Scotland
This disease has not been identified in Scotland, nor is there any evidence to date of TSEs in deer in the UK. However if it were to become established in the wild deer population it would have major consequences for the UK deer industry.
A leaflet has been produced by Scottish Natural Heritage in partnership with the Scottish Government and other members of the CWD Expert Working Group which is aimed at raising awareness of the disease among key target groups, including hunters from the UK who visit North America, hosts and sporting agents who have guests from North America, and border control staff. The leaflet can be found at the following link - http://www.snh.gov.uk/docs/A2017222.pdf
You can help prevent the disease by practising strict biosecurity on your premises.
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.
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 is a TSE suspect. The vet will restrict the movement of the animal from the farm and will periodically 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.
If tests confirm a TSE infection
If these tests confirm TSE, there will be further investigations of your herd and additional disease control measures may be put in place.
You will be paid compensation for a deer which is compulsorily killed because it is suspected of being affected with a TSE. The amount paid is based on the market value of the animal at the time it was killed.