Alzheimer’s disease (AD) is a major brain disease, afflicting about 18 million elderly people worldwide. This figure will rise with increasing longevity, so there is an urgent need for effective treatment. The brains of AD sufferers contain many abnormal deposits called plaques and tangles, which are thought to play a crucial role in the disease. However, the causes of their formation and of the disease itself are unknown.
We have been investigating whether a common virus has a role in AD. We found that many elderly people harbour this virus within their brain but only those who have a specific genetic factor are at risk of developing AD. Subsequently we discovered that the viral DNA is located specifically within plaques; also, infection with this virus causes production of the main components of plaques and tangles (called beta-amyloid and abnormal tau), indicating that the virus might be a cause of these abnormal deposits.
Our recent experiments with antiviral agents indicate that they might be an effective treatment to slow AD progression in that they decrease the levels of beta-amyloid and abnormal tau which the virus induces. Also, the future possibility exists of prevention of the disease by vaccination against the virus.