Psience Quest

Quote:For decades, the idea that a bacteria or virus could help cause Alzheimer’s disease was dismissed as a fringe theory. But not so much anymore. On Wednesday, a team of researchers from Harvard Medical School reported in the journal Neuron the latest bit of evidence suggesting herpesviruses can spark the cascade of events that leads to Alzheimer’s disease, a fatal form of dementia that afflicts at least 5 million Americans.

The researchers studied how neurons in mice responded to the presence of herpes simplex 1 (HSV-1), the virus that causes cold sores. In a separate experiment involving a 3D model of the human brain grown in a dish, they also studied human herpesvirus 6 (HHV-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.