Could Alzheimer’s and Dementia Symptoms be Caused by a Viral or Bacterial Infection?

Could Alzheimer’s and Dementia Symptoms be Caused by a Viral or Bacterial Infection?When it comes to “the common cold”, research now shows it may be anything but “common”. Medical studies reveal that certain viral and bacterial infections – including respiratory infections – can actually cause damage to your brain, leading to dementia symptoms (memory loss, poor concentration, and even Alzheimer’s disease). If you’ve been looking for a motivation to begin a healthy lifestyle, protecting your memory may be just what you need. Perhaps it’s time to start that new health kick and get your immune system in top-notch shape!

When it comes to Alzheimer’s, the focus seems to be on controlling beta amyloid plaques, a hallmark of the disease found in the autopsied brains of Alzheimer’s victims. Research shows a correlation between the amount of beta amyloid and the severity of Alzheimer’s. But, as it turns out, beta amyloid plaques may be a necessary response to infection, designed to rid the brain of viruses and bacteria.

In fact, in 2010 drug makers had to abandon an experimental drug that cleared beta amyloid plaques because participants receiving the drug worsened significantly compared to those receiving the placebo. Going after beta amyloid plaques may be like going after the smoke instead of the fire.

Studies suggest several infectious agents play a significant role in the development of Alzheimer’s, and tactics aimed at reducing the infection may be more successful in slowing or stopping the progression of Alzheimer’s than attempting to eliminate the beta amyloid plaques. 

Lyme Disease and Alzheimer’s

A 2011 data review found a statistically relevant association between chronic spirochetal infection and Alzheimer’s.[1] Spirochetes are the spiral-shaped Borrelia bacteria that infect the body and sometimes the nervous system. The most common are Borrelia burgdorferi, also known as Lyme disease. Autopsies showed spirochetes were observed in the brain in more than 90 percent of Alzheimer’s deceased Alzheimer’s patients, making it 13 times more frequent in those with Alzheimer’s than in the controls. Researchers suggest the inflammation from a spirochete infection causes amyloid beta plaque to accumulate, playing a role Alzheimer’s. They also say a spirochete infection can occur years or decades before dementia manifests, and that antibiotic and anti-inflammatory therapies may be appropriate treatments for dementia in these situations.

Herpes Simplex and Alzheimer’s

Much research in recent years has linked herpes simplex virus 1 (HSV1), the virus associated with cold sores, to Alzheimer’s disease. Individuals with Alzheimer’s show a dramatic increase in antibodies to HSV1 compared to healthy control subjects. Studies also show 90 percent of adults carry the virus in their brains, which can periodically reactivate, causing persistent brain inflammation. Also, having the ApoE4 gene, the gene that raises one’s risk for Alzheimer’s, increases the likelihood of the virus residing in the brain. Researchers have found HSV1 DNA within beta amyloid plaque in the brain and suggest it is a major cause of plaques and that antiviral agents may be an appropriate management for HSV1-linked Alzheimer’s.[2]

Other Viruses Associated with Alzheimer’s

Other viruses associated with Alzheimer’s include herpes virus 6, which causes roseola in childhood, HIV, hepatitis C, and cytomegalovirus (a cause of a mono-like illness). HIV causes a type of dementia that has been found to more commonly affect those carrying the ApoE4 gene.

Bacterial Infections and Alzheimer’s

The bacteria that causes pneumonia and other respiratory infections such as Chlamydia pneumonia causes amyloid deposits when injected into the brains of mice and is therefore implicated in Alzheimer’s. Carrying the ApoE4 gene increases vulnerability.

Prevention and Solutions for Infection-Based Alzheimer’s

The role of viral and bacterial infections in Alzheimer’s opens up new avenues of exploration for treatment, especially in the realm of natural medicine. It also may help further explain why the “golden bullets” of Alzheimer’s prevention—a healthy, lower-carb diet, healthy fatty acids, stable blood sugar, regular exercise—work so well in preventing the disease. They are the same tools one can use to lower inflammation, shore up the immune system, and protect the brain from infectious invaders in the first place. Many nutritional compounds have also proven extremely effective in increasing resistance to viruses and eradicating harmful bacteria.

So, with cold and flu season just around the corner, now is the perfect time to begin employing these “golden bullet” strategies. To get started, download our FREE report, Natural Health 101: Living a Healthy Lifestyle.  Our FREE report contains a healthy eating plan, exercise tips, and vitamin and supplement recommendations.  It is much more difficult to treat an infection than prevent it – so download the report today and start boosting your immunity and protecting the health of your brain.


[1] Alzheimer’s disease – a neurospirochetosis. Analysis of the evidence following Koch’s and Hill’s criteria. Journal of Neuroinflammation 2011, 8:90 doi:10.1186/1742-2094-8-90. Published: 4 August 2011

[2] Alzheimer’s and herpes simplex virus: a link? David Perlmutter, MD. Huffingtonpost.com. January 21, 2011.

[3] Could Alzheimer’s dementia be caused by a virus? Emily Deans, MD. Psychology Today. October 11, 2011.


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UHN Staff

University Health News is produced by the award-winning editors and authors of Belvoir Media Group’s Health & Wellness Division. Headquartered in Norwalk, Conn., with editorial offices in Florida, Cleveland, Pittsburgh, … Read More

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