The idea that microbial pathogens contribute to chronic illness is not new or outlandish.  The importance of chronic infection and the host of microorganisms involved are grossly overlooked topics in medicine. Helicobacter pylori for example is a chronic bacterial infection that can cause gastric ulcers as well as cancer.  Clearly, certain strains of the Human Papilloma Virus (HPV) cause cervical cancer, which has resulted in the development of an HPV vaccine.  In the early 1900’s, rheumatoid arthritis was thought to be an infectious disease.  The departure from this sort of thought process may be one of the most significant wrong turns on the road of medicine.  It isn’t unrealistic to think that Chlamydia pneumoniae (or one of its newly described cousins dubbed Chlamydia-like Organisms [CLOs]) is a significant player in diseases where there currently is substantial evidence: Alzheimer’s, Coronary Artery Disease, Arthritis, Asthma, and MS.

Why have Chlamydiae been researched so heavily in correlation with chronic diseases?  Because they are virulent, stealthly, parasitic, and have the cability to elicit a pro-inflammatory immune response.  Oh, and they can travel throughout the body.  Like HIV, Chlamydia has the ability to infect the immune system.  CLOs and Chlamydia pneumoniae infest cells all over the body, pirate ATP from our mitochondria, and substantially delay apoptosis.  In simple terms, things don’t work properly when Chlamydia is hanging out.  Unfortunately for all of us, Chlamydia pneumoniae is an extremely prevalent respiratory infection transmitted to half of us by the age of 20 and most of us by the age of 80.  Kind of makes you want to hold your breath when someone coughs in the elevator, doesn’t it?

In addition to Chlamydia pneumoniae and the better-known sexually transmitted infection, Chlamydia trachomatis, other important Chlamydiae and CLOs have been discovered.  Simkania negevensis, Waddlia chondrophila, and Chlamydia psittaci are all able to gain entry via the respiratory system and hunker down.

More research, particularly long-term antimicrobial trials, are needed to assess the impact of these pathogens in the above diseases (and others).  The idea that one day we could vaccinate against Alzheimer’s and Asthma is not farfetched.  However, this concept needs to be acknowledged before that ever becomes a reality.