A viral infection of the eye may be the culprit in a common form of blindness in seniors, Georgia State University researchers have found.
The researchers, writing in the journal Public Library of Science Pathogens, said they have determined the condition – known as neovascular age-related macular degeneration (AMD) – is caused by cytomegalovirus, a type of herpes virus.
"Prior to this work, cofactors for the development of AMD included genetics, a high fat diet and smoking,” noted lead researcher said Richard D. Dix, of the Georgia State Viral Immunology Center's Ocular Virology and Immunology Laboratory. “Now, we are adding an [infectious] agent as another cofactor."
About 80 percent of Americans have antibodies for the herpes virus, which is often acquired during childhood. A normal, healthy immune system can keep the virus in check. But as people age, the immune system's function is reduced, and the virus proliferates, causing the processes that lead to AMD.
Identifying the virus as a factor in the development of AMD paves the way for potential new treatments, Dix said. One option: Reducing the amount of the virus in the blood stream with an antiviral drug such as ganciclovir.
The research was funded, in part, by the National Institutes of Health.