Seasonal Canine Illness

Seasonal Canine Illness

Seasonal Canine Illness (SCI) is a mysterious illness which can afflict dogs in the autumn after they have been walking in woodland. The illness can affect dogs of any breed and may prove fatal. The cause has yet to be confirmed. It was thought that bacteria, blue-green algae or fungal spores could be responsible but these have now largely been ruled out. The focus of scientific research is now on harvest mites. Harvest mites are red mites which are the size of a pin head and usually infest dogs' feet. The mites can cause paws to become very itchy. Several dogs which have contracted SCI have been found to have these mites and so it is possible that infestation is linked to the disease but no firm correlation has been established. It has also been suggested that dogs may be more susceptible to SCI after long journeys in the car or if they have become dehydrated.

The Symptoms

The most common symptoms of SCI are sickness, diarrhoea and lethargy. Dogs typically begin to display symptoms roughly 72 hours after walking in woodland. If your dog shows signs of becoming ill then you should seek veterinary advice immediately. Survival rates appear to be improving and this is probably because an increased awareness of the disease has led to earlier medical interventions. The latest information strongly suggests that dogs which receive treatment quickly have a much better chance of recovery.


Even the Royal estates are not immune to Seasonal Canine illness. At Sandringham, where the disease was first identified in 2009, there are now warning signs for dog owners. Last year 15 dogs were thought to have contracted SCI at the estate in a single month. Owners expressed anger that they had not been warned of the dangers. Visitors to the Sandringham Estate are being told to keep their dogs on leads and under close control. They are also being advised to seek topical treatments for harvest mites as these may be the carriers of the disease. The Queen is reported to have personally requested that the disease be investigated. However, royal shooting parties are continuing to use dogs to retrieve birds during shooting parties.

Danger Zones

Numerous cases of SCI have also been reported in Sherwood Forest, Nottinghamshire and it has struck in Cornwall, Surrey, Suffolk, Worcestershire and Co Durham. But these areas are hotspots and the dogs could contract the disease anywhere. Other than protecting your dog from harvest mites, there is little that you can do to protect your pet from SCI. You could avoid walking in woodland and parkland areas between August and November, but this would be rather drastic action to take. Most dogs will recover from SCI if they are treated in a timely manner so it is vital that you monitor your dog and take action if they appear to be unwell.

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