Memory Loss May Be Caused by Common Infections

by Dorian Martin Patient Advocate

When people start experiencing memory loss, they (and their loved ones) often jump to the conclusion - "It's Alzheimer's It's Dementia!" But these cognitive issues may not be related to dementia at all. As I have mentioned before, I've seen my father periodically experience memory loss. In his case, it's not Alzheimer's disease; instead, it's been due to misuse of his medications or low blood oxygen levels.

Now researchers are finding that common infections also may have an effect on memory as well as other cognitive issues, such as mental processing, abstract thinking, planning as well as reasoning. In this new study out of the University of Miami and Columbia University, researchers followed 588 participants, most of whom were Hispanic. These people, who took part of the Northern Manhattan Study, participated in brain function tests and also had their blood samples taken at the start of the study. At the five-year mark, about half of the participants took another cognitive test. The researchers found that participants who had increased infections in their blood had a decline in cognitive function, even if they never became ill.
Researchers are not sure why these infections have an effect on cognitive function.

The bacteria that the researchers identified were:

  • Chlamydia pneumonia - This type of bacteria commonly shows up in pneumonia, bronchitis and a cough, but with little or no fever; however, this bacteria less commonly shows up in paryngitis, laryngitis and sinusitis. Someone who has this type of bacterial infection can run the gamut - they may not have any symptoms or they can develop a major disease.
    The Centers for Disease Control and Prevention report that this infection is transmitted between people through respiratory secretions.

  • Helicobacter pylori - This type of bacteria infects the stomach and usually happens during childhood.
    The most common condition associated with Helicobacter pylori is a peptic ulcer. Again, most people do not realize that they have an infection from this type of bacteria. This type of bacteria is passed between people through direct contact from saliva, vomit or feces, or through contaminated food or water.

  • Cytomegalovirus - This is a common virus that can strike people at any age. Like the previous types, many people who have this virus don't show any symptoms. The virus is most often passed between people through direct contact with body fluids, including sexual contact. The virus also can develop after blood transfusions and organ transplants.

  • Herpes simplex viruses 1 and 2 - These infections are also very common. Herpes simplex virus 1 often shows up through cold sores, fever blisters and other infections on the mouth and lips. Signs of this virus also can include a sore throat, swollen lymph nodes in the neck, fever, and tingling around the mouth or nose. This infection is transmitted through sharing saliva, whether through kissing or using the same drinking glasses. This version also can result in genital herpes.
    Herpes simplex virus 2 is spread through sexual contact. Symptoms for both types of herpes can be triggered through fever, emotional stress, a weak immune system, sun exposure or an illness. There is no cure for either type of these viruses.

While the researchers have not found evidence that treating these infections will benefit cognitive ability, I think it would behoove everyone to try to avoid contracting these infections, if at all possible. Some steps you can take include the following:

  • Not sharing personal items, like glasses or toothbrushes.

  • Frequently wash your hands with soap and water.

  • Reduce stress levels.

So if you or a loved one begins to experience cognitive issues, don't immediately jump to that conclusion that it's Alzheimer's disease. Know that the reasons for memory loss can actually be due to bacteria and the resulting infection or some other reason. Therefore, I'd encourage everyone to work with their doctor to try to determine what exactly is behind any cognitive issues that have emerged.

Primary Sources for This Sharepost:

American Heart Association. (2014). Common infections may increase risk for memory decline

Centers for Disease Control and Prevention. (2010). Cytomegalovirus (CMV) and congenital CMV infection.

Mayo Clinic. (2011). H. pylori infection.

University of Maryland Medical Center. (2011). Herpes simplex virus.

Dorian Martin
Meet Our Writer
Dorian Martin

Dorian Martin writes about various topics for HealthCentral, including Alzheimer’s disease, diet/exercise, menopause and lung cancer. Dorian is a health and caregiving advocate living in College Station, TX. She has a Ph.D. in educational human resource development. Dorian also founded I Start Wondering, which encourages people to embrace a life-long learning approach to aging. She teaches Sheng Zhen Gong, a form of Qigong. Follow Dorian on Twitter, Facebook or Instagram at @doriannmartin.