Encephalitis is divided into bacterial encephalitis and viral encephalitis. Generally, viral encephalitis has a lower mortality rate than bacterial encephalitis. The main reason for the high mortality rate of bacterial encephalitis is that many drugs cannot penetrate the blood-brain barrier. At the same time, bacterial encephalitis is discovered late, which is also one of the important reasons for the high mortality rate.

Dog encephalitis may be caused by pathogenic infection, such as purulent bacterial infection, rabies virus, canine distemper virus infection, systemic sepsis caused by other parts of the body, and migration of parasites to the brain. .