European researchers pored over hundreds of thousands of medical records to determine the role that severe viral infection may play in the development of neurodegenerative diseases. As a result of the study, scientists suggest that vaccinations against viruses may reduce the risk of these neurological disorders such as Alzheimer’s, Parkinson, and ALS.
Researchers have found that there was a link between Alzheimer’s and six different viruses.
Existing vaccines, like the flu vaccine, may help reduce the risk of being hospitalized and triggering Alzheimer’s disease or other neurodegenerative disorders.
Researchers studied the medical records of around 35,000 Finnish people with six different types of neurodegenerative diseases. They then compared them to a group of 310,000 people with no sign of brain diseases. Researchers then checked if the patients with neurodegenerative disorders had a history of being hospitalized for a viral infection.
In addition, scientists further performed a second analysis of around 100,000 records in the United Kingdom.
Among the neurodegenerative disorders, researchers found that there was a link between Alzheimer’s and six different viruses. These include viral encephalitis, viral warts, influenza, and viral pneumonia. Furthermore, results showed that people with Alzheimer’s were 20 times more likely to have been hospitalized for viral encephalitis than those without the disease.
“The overwhelming majority of replicated associations include viruses commonly considered neurotrophic (81%), which means they can invade the central nervous system through peripheral nerves or by crossing the blood-brain barrier. This suggests that these viruses may increase neurodegenerative disorder risk by lowering resilience to neurodegeneration and the ability to carry out complex mental tasks by contributing to inflammation in the brain,” researchers wrote.
Alzheimer’s Disease Prevention Through Vaccination?
The study also raises the possibility that existing vaccines, like the flu vaccine, may help reduce the risk of being hospitalized and triggering Alzheimer’s disease or other neurodegenerative disorders.
“Strikingly, vaccines are currently available for some of these viruses, including influenza, shingles and pneumonia. Although vaccines do not prevent all cases of illness, they are known to dramatically reduce hospitalization rates. This evidence suggests that vaccination may mitigate some risk of developing neurodegenerative disease,” researchers wrote.
Inflammation in the Nervous System and Disease
While this study cannot pinpoint the causal link, it adds to ongoing research exposing the role of viruses in Parkinson’s and Alzheimer’s disease.
“Neurodegenerative disorders are a collection of diseases for which there are very few effective treatments and many risk factors,” said co-author Andrew Singleton, a neurogeneticist and Alzheimer’s researcher and the director of the Center for Alzheimer’s and Related Dementias.
“Our results support the idea that viral infections and related inflammation in the nervous system may be common – and possibly avoidable – risk factors for these types of disorders,” researchers concluded.
This study was published in Neuron, and it’s worth checking out if you’re interested in learning more!
Become an Insider and stay up to date on Alzheimer’s and dementia breakthroughs.