Study links viral infections to Alzheimer ’s, Parkinson’s—with many caveats

A massive data mining study has found numerous associations between common viruses like the flu and devastating neurodegenerative disorders such as Parkinson’s disease, Alzheimer’s disease, and amyotrophic lateral sclerosis (ALS, also known as Lou Gehrig’s disease). The findings expand on previous research linking individual viruses to neurological diseases. But experts caution that the study, which relied on electronic medical records rather than biological samples, merely describes correlations and doesn’t prove causation. Still, it’s “really exciting,” says Kristen Funk, a neuroimmunologist who studies Alzheimer’s at the University of North Carolina, Charlotte. Rather than homing in on, say, the relationship between herpes simplex infections and Alzheimer’s—a recent focus in her own field—“this research broadens that scope to look at different viruses and more neurodegenerative diseases.” Scientists have found connections between viruses and neurodegenerative diseases before. Previous studies uncovered ties between the influenza virus and Parkinson’s, for example, and between genital warts (caused by human papillomavirus) and dementia. A landmark project published in Science last year cemented another connection: Epidemiologists who analyzed 2 decades of data from the blood tests of 10 million U.S. soldiers reported that it’s nearly impossible to develop multiple sclerosis without first being infected with the Epstei...
Source: ScienceNOW - Category: Science Source Type: news