SEASONAL CANINE ILLNESS (SCI)
The AHT has been investigating Seasonal Canine Illness (SCI) since September 2010.
Cases of this mystery illness are generally seen between August and November. SCI can affect dogs of any size, shape or sex and it causes dogs to become very ill, very quickly after being walked in woodland.
The most common clinical signs are sickness, diarrhoea and lethargy. If you suspect your dog is showing signs of SCI then please contact your vet immediately.
On these web pages you will find information on our SCI investigation along with a questionnaire that we need dog owners to complete.
If you have walked your dog in any of our five study sites: Sandringham Estate or Thetford Forest, Norfolk, Sherwood Forest or Clumber Park, Nottinghamshire or Rendlesham Forest, Suffolk, please complete our online questionnaire – regardless of whether your dog was taken ill or not.
![]() |
![]() |
To download our seasonal canine illness information sheet, please click here.









