Alzheimer’s disease affects 44 million people worldwide, including 5 million Americans over the age of 65. It is a progressive and debilitating form of dementia. Research is ongoing to find its causes, as well as prevention and treatment methods. One of the controversial theories out there is that Alzheimer’s is caused by a virus or multiple viruses that attack the brain. (1, 2, 3) 

A new study asks the question. Could herpes impact Alzheimer’s?

What is Alzheimer’s?

Alzheimer’s is the most common type of dementia. It is a serious and progressive disease. It starts with mild memory loss ending up with a debilitating condition when one loses their ability to carry on basic conversations, remember people and events, respond to the environment and do basic daily activities. Alzheimer’s affects one’s thoughts, memory and language. (1)

Alzheimer’s and Herpes Strains: New Study

According to a recent study published in the Neuron journal, people with Alzheimer’s had a higher level of viruses affecting the brain than those without. Specifically, those with Alzheimer’s had a significant amount of herpes virus in their brain, more distinctively, two common strains of it.

Researchers believe that viruses and other pathogens could affect brain health and the development of Alzheimer’s. This is not a new theory but was first talked about in the 1950s.

Dr. Benjamin Readhead and his research team became interested in this idea and went down the rabbit hole between the relationship of viruses and Alzheimer’s. They analyzed the brain and genetic data of 1,000 people, some with Alzheimer’s and some without. They compared this genetic data to 500 viruses that affect humans.

Despite the fact that other research has pointed out the possible role of herpes simplex virus one (HSV1), the idea that a virus or other pathogen can play a role in Alzheimer’s has been controversial.

The new study has found that two strains of herpes – herpes 6A and 7 – may be the ones that are connected to Alzheimer’s. The interesting fact is that most people carry these strains since infancy. They usually go undetected since they don’t tend to cause problems other than occasional rashes in some younger children. Though the virus was present in 40 – 50 percent of all samples, those with Alzheimer’s had significantly more copies of the virus. (4, 5, 6)

What Is The Link Between Alzheimer’s and Herpes?

It is impossible to tell if these herpes strains can actually cause Alzheimer’s since it can be found in those with and without the disease. However, researchers believe that there may be a connection. There seems to be an important mechanism that needs to be looked at that may affect someone’s response to the virus.

These strains of herpes may be that one possible cause of the disease, a part of the cause, or may simply accelerate the progression of Alzheimer’s. There may also be a chance that it has no role in the disease at all, but simply there for the ride to complicate one’s health. It seems that the herpes virus, in particular its 6A strain, has interacted with certain genes related to the amyloid plaques in the brain. Further research is essential to evaluate its true role and function. (4, 5, 6)

Response from Other Researchers

Though some researchers are skeptical, other scientists have been impressed by these new developments. Hugo Lövheim, a senior lecturer in the Department of Community Medicine and Rehabilitation at Umea University in Sweden, has been particularly excited about the in-depth analysis, using bioinformatic techniques, bringing more knowledge to support the increasing evidence in the role of viruses in Alzheimer’s. He noted that the HSV1 seems to affect the disease at its onset, whereas the 6A strain may play a role at later stages. Lövheim has urged further research, including drug research targeting both strains. (6, 7)

The first researcher who has studied HSV1 as a possible cause of Alzheimer’s in 1991, Ruth Itzhaki, a professor emeritus of neuroscience and experimental psychology at the University of Manchester, believes that the link between HSV1 and Alzheimer’s is stronger than the relationship between 6A and the disease. However, she is happy to see that the possible connection between viruses and Alzheimer’s taken seriously by some researchers in current times. (6, 8, 9)

What’s Next?

The bottom line is that further research is essential to understand the potential connection between various strains of the herpes virus, other possible viruses and pathogens and Alzheimer’s disease. Still further, to understand how this may play a role in prevention and treatment. It is fascinating and holds a lot of hopeful potential.

What do you think about this new research? Do you know anyone with Alzheimer’s? Share your thoughts and experiences in the comments. We want to hear from you.

References:

1. https://www.cdc.gov/aging/aginginfo/alzheimers.htm
2. https://www.alz.org/alzheimers-dementia/facts-figures
3. https://alzheimersnewstoday.com/alzheimers-disease-statistics/
4. https://www.cell.com/neuron/fulltext/S0896-6273(18)30421-5
5. https://www.livescience.com/37541-cytomegalovirus-alzheimer-disease-cmv.html
6. https://www.livescience.com/62883-herpes-viruses-alzheimers.html
7. https://www.umu.se/en/staff/hugo-lovheim/
8. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4128394/
9. https://www.research.manchester.ac.uk/portal/ruth.itzhaki.html