Shireen Dooling for the Biodesign Institute at ASU

HHV 6A and 7 are common herpesviruses to which most are exposed as children. The two viruses were detected in higher abundance in brains with Alzheimer's disease and their activity appears related to certain hallmarks of the disease.

Viruses acquired early in life could play a role in Alzheimer’s disease. That’s according to a new study, which came out Thursday. The findings could change how scientists look for ways to treat or prevent Alzheimer’s.

The research team, which includes Ben Readhead of the Banner ASU neurodegenerative disease research center, found that two common herpes viruses might be linked to Alzheimer’s disease:

"HHV6a, which is one of the most interesting ones to come out of this study, we saw it regulating a large number of Alzheimer’s risk genes and we also saw it regulating a large number of proteins that regulate amyloid production and amyloid is the main ingredient in these sticky amyloid plaques that accumulate in the brains of people with Alzheimer’s disease," Readhead said.

He said the team found more viral genetic material in Alzheimer’s affected brains versus normal ones.

"What we found in particular to Alzheimer’s disease was an increased abundance of two particular herpes viruses: HHV6a and HHV7, which haven’t previously been linked to Alzheimer’s disease."

Readhead says around 90 percent of children in the U.S. and the U.K. are exposed to these viruses in the first few years of life. The findings don't prove the viruses cause Alzheimer's, nor do they suggest it's contagious.

The findings don’t prove viruses cause Alzheimer’s, nor do they suggest it’s contagious. 

Ben Readhead/Neurodegenerative Disease Research Center, Arizona State University

Graphic of interactions between viruses and different levels of host biology, to understand the relevance of viruses to Alzheimer's disease.