Mouth virus one in five Britons get doubles risk of dementia, new study confirms - symptoms start in 48 hours

Composite image of a mouth virus next to a brain scan

Oral herpes doubles your risk of dementia, confirms new study

Getty Images
Adam Chapman

By Adam Chapman

Published: 16/02/2024

- 11:34

The latest research, published in the Journal of Alzheimer's Disease, could have implications for millions of Britons

People who have had oral herpes at some point in their lives are twice as likely to develop dementia compared to those who have never been infected, warns an alarming new study.

The new study from Uppsala University builds on previous research that explored whether herpes can be a possible risk factor for dementia.

Oral herpes, also known as cold sores, affects around one in five people in the UK.

It's caused by the herpes simplex virus, and is usually caught by coming into contact with someone who has it - for example, by receiving a kiss on the mouth.

Oral herpes is transmitted by coming into contact with someone who has it, for example - by kissing

Getty Images

The main symptom of oral herpes is cold sores: red, painful blisters that develop around the mouth.

Lloyds Pharmacy explains further: "To begin with you might notice a tingling or itching feeling in the skin around your mouth

"Over the course of about 48 hours, a cold sore will appear in the area. It will usually remain for around 10 days. During this time it should burst, scab and heal on its own."

The connection to dementia

For the latest study, published in the Journal of Alzheimer's Disease, researchers studied 1,000 70-year-olds from Uppsala over a period of 15 years.

The participants underwent assessments at the ages of 70, 75, and 80 years.

At the age of 85 years, they were followed through medical records.

Serum samples were taken from the participants at the start of the study to detect herpesvirus antibodies and this was compared with the incidences of dementia that occurred over the course of the study.

What did the researchers find out?

Alzheimer's disease and other forms of dementia were diagnosed in four percent and seven percent of the participants, respectively.

This led researchers to conclude that the presence of herpes virus antibodies doubles the risk of dementia, though they could not prove a causal link.

“What’s special about this particular study is that the participants are roughly the same age, which makes the results even more reliable since age differences, which are otherwise linked to the development of dementia, cannot confuse the results,” explains Erika Vestin, a medical student at Uppsala University.

Old man gripping his head in pain

Researchers are now looking into whether known drugs against the herpes simplex virus can reduce the risk of dementia

Getty Images

Research has previously been conducted to investigate whether the herpes simplex virus could also be a possible risk factor for dementia; something now confirmed in this study.

“It is exciting that the results confirm previous studies. More and more evidence is emerging from studies that, like our findings, point to the herpes simplex virus as a risk factor for dementia,” continued Ms Vestin.

Important conclusions from the study include the need to further investigate whether already known drugs against the herpes simplex virus can reduce the risk of dementia and the possibility of developing new vaccines.

“The results may drive dementia research further towards treating the illness at an early stage using common anti-herpes virus drugs, or preventing the disease before it occurs,” added Ms Vestin.

How can I reduce my risk of oral herpes?

Unfortunately, there’s no cure for herpes, but you can treat your treat it with over-the-counter medicines, says Lloyds Pharmacy.

Naturally, prevention is better than a cure, and the best way to prevent oral herpes is to avoid contact with people who have visible sores on their face.

"Just be aware that oral herpes can be contagious even before a sore appears, so it’s not always easy to avoids," Lloyd Pharmacy adds.

You may like