According to a new Tufts University study, the combination between herpes and varicella might be responsible for people developing Alzheimer’s disease in their later years.
This is worrying because these are two really common viruses but fortunately, it appears that vaccines do work in reducing the risk.
Co-author Dr. Ruth Itzhaki also shared that “age and the decline in the immune system with age, and immunosuppression” are main factors that are able to reawaken VZV as shingles in adults.
Prior to this study, “VZV has been linked to AD, but the linkage was unclear, and the mechanisms not understood,” Dr. Itzhaki, added.
What the team of researchers learned was that when VZV becomes activated as shingles, it also reactivates dormant herpes virus type 1, also referred to as HSV-1.
HSV-1 is really common as well, with 50 to 80 percent of American adults carrying it.
“What is known is that infectious diseases, confer a risk of AD, and our results explain this for shingles. We’re now investigating if it’s the case for some other infections. If it is, then it’d explain the major risk posed by infectious diseases,” Itzhaki shared with Kaplan adding that “If we shift paradigms to focus our efforts more on preventive strategies of treating the microbial species before they get a chance to wreak havoc, we might have a much better handle on preventing this disease.”
Dr. Itzhaki stressed that “Thirty years of evidence from my lab, and subsequently from many others, suggests that HSV-1 is a major cause of AD, although the disease is obviously multifactorial.”
Furthermore, an assistant professor of psychiatry at the University of Pittsburgh School of Medicine, Tharick Pascoal, who wasn’t involved in the study, reacted to the results.
Dr. Pascoal thinks the research adds a lot to the already existing evidence that HSV-1 can lead to neuroinflammation, which is, indeed, linked to a higher risk of developing Alzheimer’s disease.