Final answer:
Blue eye, or corneal edema, in canines is often associated with canine adenovirus or vaccinations against it. Canine adenovirus can cause viral conjunctivitis, which can lead to inflammation of the eye's structures, resulting in blue eye.
Step-by-step explanation:
Blue eye, or corneal edema, is a term often used to describe a condition that can occur in canines as a result of canine adenovirus or after vaccination against that disease. Canine adenovirus is known to cause various conditions, including viral conjunctivitis. This condition can be part of a more generalized infection that affects multiple organs and can lead to the inflammation of the conjunctiva (conjunctivitis) or cornea (keratitis), which may result in the symptom known as blue eye. When it comes to corneal conditions such as keratitis, various viruses, including adenoviruses and herpes simplex virus 1, can be the culprits. While herpes simplex virus 1 is a known cause of human eye infections, adenoviruses are commonly associated with canine viral conjunctivitis. The adenovirus causes liver cells to secrete toxins that damage endothelial cells in the cornea leading to corneal edema or 'blue eye.'