Studies have shown that the amount of virus circulating in an individual's blood is associated with
the rate of disease progression.
While the loss of cognitive ability is irreversible,
the rate of disease progression varies by individual.
The age of onset of clinical signs can range from months to years and
the rate of disease progression and its severity also varies significantly.
Although there is individual and breed variation in the age of onset and
the rate of disease progression, the disease eventually progresses to complete blindness in most dogs.