MAPT and viral infectious disease: Many hypotheses have been proposed to underlie the development of AD, including (i) amyloid beta aggregation, (ii) tau hyperphosphorylation, (iii) neuroinflammation, (iv) neurotransmitter dysfunction, (v) mitochondria dysfunction, (vi) glucose metabolism, (vii) vascular dysfunction and (viii) viral infection [485,487,488,489].