The virus which causes cold sores can be linked to brain changes which happen during the onset of Alzheimer's disease, according to scientists from the north-west.
A team from the University of Manchester found that as a result, the use of standard anti-viral drugs could be adapted to fight off or prevent the disease from taking hold.
The facial marks are linked to herpes simplex virus type 1 (HSV1), which has been found present in the brains of Alzheimer's disease sufferers.
Leader of the study Professor Ruth Itzhaki said the HSV1 virus causes "severe" damage to brain cells and results in their disintegration.
She continued: "We suggest that HSV1 enters the brain in the elderly as their immune systems decline and then establishes a dormant infection from which it is repeatedly activated by events such as stress, immunosuppression, and various infections."
According to the Alzheimer's Society, 417,000 people suffer from the condition in the UK.
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