It is well known that systemic infections cause flare-ups of disease in individuals with asthma and rheumatoid arthritis, and that relapses in multiple sclerosis can often be associated with upper respiratory-tract infections. Here we review evidence to support our hypothesis that in chronic neurodegenerative diseases such as Alzheimer's disease, with an ongoing innate immune response in the brain, systemic infections and inflammation can cause acute exacerbations of symptoms and drive the progression of neurodegeneration.
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Work in the authors' laboratories was supported by the Alzheimer's Research Trust, the UK Medical Research Council, and the Wellcome Trust.
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Perry, V., Cunningham, C. & Holmes, C. Systemic infections and inflammation affect chronic neurodegeneration. Nat Rev Immunol 7, 161–167 (2007). https://doi.org/10.1038/nri2015
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