Summary of “Yet More Evidence that Viruses May Cause Alzheimer’s Disease”

For decades, the idea that a bacteria or virus could help cause Alzheimer’s disease was dismissed as a fringe theory.
In a separate experiment involving a 3D model of the human brain grown in a dish, they also studied human herpesvirus 6, the germ responsible for causing the childhood skin disease roseola.
These viruses are usually caught early on in life and stay dormant somewhere in the body, but as we age, they almost always migrate up to the brain.
The mice’s brains grew new deposits of amyloid-β plaques practically “Overnight,” according to senior author Rudy Tanzi, a geneticist specializing in the brain at Massachusetts General Hospital as well as Harvard Medical School.
The study is the second in recent weeks to support the role of viruses in Alzheimer’s disease.
That first study, also published in Neuron and led by researchers from the Icahn School of Medicine at Mount Sinai, found evidence that certain herpesviruses are more abundantly present in the brains of people who died with Alzheimer’s; it also suggested that genes belonging to these viruses directly interact with human genes that raise the risk of the disease.
From there, Tanzi’s work has shown, the plaques trigger the production of tangles-clumps of another brain protein called tau seen in the later stages of Alzheimer’s-which together then trigger chronic inflammation.
Genetics might help explain why only some people’s infections cause the brain to start producing amyloid-β en masse.

The orginal article.