Common cold sores increase Alzheimer's risk By Alfred Kristoffer A. Guiang firstname.lastname@example.org | Oct 26, 2014 10:24 PM EDT Caught a cold sore lately? Then, you are a more likely candidate for Alzheimer's than someone who never had cold sores in his or her lifetime. This was what researchers from the Umea University in Sweden discovered when they studied the correlation between Herpes Simplex infections like cold sores and Alzheimer's disease. The study said that when a person gets infected by the herpes simplex virus, he or she may or may not exhibit the symptoms such as blisters around or inside the mouth, but the person becomes a carrier all throughout his or her life. The herpes virus, once reactivated, eventually weakens the body's immune system which, in turn, enables the virus to spread to the brain where it leads the person towards dementia, the researchers explained. The link between the two illnesses has been confirmed by two epidemiological studies conducted by the team. In one study, the researchers followed 3,432 participants for an average of 11.3 years. They found that having certain antibodies against herpes virus doubled the chances of acquiring Alzheimer's disease. The other study involved 360 people with Alzheimer's disease and an equal number of controls. They took blood samples on average 9.6 years before the disease was diagnosed in them. Then, they took samples of the people taken 6.6 years prior to their condition. Both were analyzed. The risk of developing Alzheimer's disease linked to the herpes simplex virus too was confirmed in the second study. Dr. Hugo Lovheim, study author and an associate professor at the Department of Community Medicine and Rehabilitation, Geriatric Medicine in Umea University in Sweden said "Our analysis reveals that the herpes virus causes a significant proportion of all cases of Alzheimer's disease - nearly 40 to 50 percent." "The study is a breakthrough. Whether the treatment of Herpes infection with antiviral drugs might slow the Alzheimer's progression is not yet known, but is definitely worth investigating in clinical studies," he explained. According to Herpes Virus Association, about six in ten people carry the herpes simplex virus, with most of them unaware of it because they have never noticed any symptoms. It said that only a quarter of the people who catch this virus will notice any symptoms at all. "Alzheimer's & Dementia" published the findings in its recent edition.