At the neuronal level, HSV-1 infection has been shown to induce tau hyperphosphorylation, amyloid-beta 40 and 42 (Aβ40/42) accumulation, oxidative stress, neuroinflammation and apoptotic dysregulation, all of which are implicated in the pathophysiology of neurodegenerative diseases such as AD. This evidence concerns the gene MAPT and Alzheimer disease.