Seasonal canine illness, often abbreviated as SCI, is a rare disease that has affected dogs from August through November. Cases of this illness were first reported in the United Kingdom in large numbers in 2018. While cases have declined since that time, there are still some occurrences every year.
In many ways, SCI is a mystery illness. It has affected dogs of many breeds, sizes, shapes, physical activity levels, and genders. The only real commonality between cases has been that dogs tend to have been in a wooded area a few days before becoming unwell.
Seasonal canine illness earned its name because it tends to occur during a specific season of the year: autumn.