A bacteria that commonly causes gum infections also seems to be causing Alzheimer's. Many scientists suspected the disease was caused by a bacterial infection, and when scientists gave P. gingivalis to mice, the rodents developed memory loss and amyloid beta plaque. A treatment is now being tested.

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A bacteria that commonly causes gum infections also seems to be causing Alzheimer's. Many scientists suspected the disease was caused by a bacterial infection, and when scientists gave P. gingivalis to mice, the rodents developed memory loss and amyloid beta plaque. A treatment is now being tested.