I have a thought that only applies to the brain - perhaps mechanical injuries which can allow viruses to cross the blood brain barrier which only happen in a sm

I have a thought that only applies to the brain - perhaps mechanical injuries which can allow viruses to cross the blood brain barrier which only happen in a small subset of the population are the ones that are more likely to develop autoimmune disease in the brain. So a car accident which leads to a tear which allows virus into the brain which leads to autoimmune disease that affects the hippocampus which manifest as physical symptoms.