Alzheimer’s disease could be caused by herpes virus
Specialists from Oxford, Cambridge, Edinburgh and Manchester Universities and Imperial College, have written a paper which suggests that bacteria and viruses, like herpes, could be the cause of Alzheimer’s disease. The worldwide team of 31 scientists and clinicians have called for an investigation into the possible link.
Two of the major culprits named are the herpes virus (simplex 1 & 2) and the chlamydia bacteria, as well as a bacteria called spirochaete (syphilis and Lyme disease are caused by spirochetes).
However, not everyone agrees with the team. From the article:
“Prof John Hardy, Professor of Neuroscience, UCL, said: ‘This is a minority view in Alzheimer research. There had been no convincing proof of infections causing Alzheimer disease. We need always to keep an open mind but this editorial does not reflect what most researchers think about Alzheimer disease.’”
and
“Dr James Pickett, Head of Research at Alzheimer’s Society said: ‘A large number of different microbes including viruses, bacteria and fungi have been found in the brains of older people – but there do appear to be more of them in the brains of people who have died with Alzheimer’s disease. While these observations are interesting and warrant further research, there is currently insufficient evidence to tell us that microbes are responsible for causing Alzheimer’s disease in the vast majority of cases. We would like to reassure people that there remains no convincing evidence that Alzheimer’s disease is contagious or can be passed from person to person like a virus.'”
“Dr Simon Ridley, Director of Research at Alzheimer’s Research UK, said: ‘There is growing evidence for the role of the immune system in Alzheimer’s and active ongoing research looking at how an inflammatory response might contribute to the disease. There is some evidence to suggest that infections in general could ramp up the immune system and contribute to the progression of Alzheimer’s, but there isn’t conclusive evidence to suggest that a particular infectious agent or microbe could be directly responsible for causing the disease.'”
But what cannot be ignored, the authors say, is that, “viruses and bacteria are common in the brains of elderly people, and although they are usually dormant, they can ‘wake up’ after stress or if the immune system is compromised”. They also show that gene mutation, APOEe4, which makes some more susceptible to Alzheimer’s- increases susceptibility to infectious disease; and as viral infections in the brain are known to cause symptoms similar to Alzheimer’s, and viruses cause systemic inflammation, and systemic inflammation is a characteristic of Alzheimer’s, it’s time to do some research in this area.
Since two thirds of people will get herpes at some point in their lives (many don’t even know) and the herpes virus is known to damage the central nervous system, and the limbic system (the part of the brain which regulates mood and instinct)- the authors feel further investigation is warranted.
This is exciting news and we will be watching eagerly in the hopes that the medical community takes this request seriously.
Source: The Telegraph
