https://journals.sagepub.com/doi/10.1177/0976500X221150310?icid=int.sj-abstract.similar-articles.2

Microbial Infection
A viral or bacterial infection has been linked to the onset of AD. H. pylori infection causes dysbiosis. When compared to non-infected patients, chronic H. pylori infection was found to promote the production of inflammatory factors and was connected to a poorer Mini-Mental State Exam (MMSE) score. Furthermore, blood levels of A1−40 and A42 are higher in AD with H. pylori, Borrelia burgdorferi, and Chlamydia pneumoniae infection. In neuroblastoma cells, exposure to H. pylori filtrate causes tau hyperphosphorylation similar to that seen in AD tau pathology.³⁹