Submitted to: Post-Infectious Sequelae Long-Term Consequences of Infectious Diseases
Publication Type: Book / Chapter
Publication Acceptance Date: March 4, 2008
Publication Date: July 1, 2009
Citation: Smith, J.L., Fratamico, P.M. 2009. Diseases with Long Term Consequences in Search of a Microbial Agent. In: Sequelae and Long-Term Consequences of Infectious Diseases. P.M. Fratamico, J.L. Smith, and Ka.A. Brogden (Ed.) Washington, D.C.: ASM Press. p. 459-475. Technical Abstract: Many infections, including food-borne infections, have long term consequences due to known infective agents. For example, Escherichia coli O157:H7 infection can lead to hemolytic uremic syndrome and Campylobacter jejuni infection can lead to Guillain-Barré Syndrome. However, there are other diseases with long term consequences (chronic diseases) that do not appear to be associated with a known infectious agent or may be suspected of having a microbial trigger, such as the association between Mycobacterium avium paratuberculosis and Crohn’s Disease. Bacterial or viral infections have been postulated to cause diseases such as rheumatoid arthritis, chronic fatigue syndrome, multiple sclerosis, as well as others; however, definitive proof of an infectious origin is lacking. It is clear that many of these diseases with an unknown infectious etiology are autoimmune diseases with a strong genetic component. It is probable that many of these diseases are not caused by a single infectious entity but rather are caused by a number of different agents and in fact, several studies on Crohn’s disease implicate a number of bacteria as causative agents. Thus, the individual who is genetically susceptible may, due to a viral or bacterial infection and the consequent inflammation, suffer the long term consequences associated with the disease. It is not always clear, however, if the detected organism is the causative agent or if the microorganism is merely present as an opportunistic pathogen because of immunosuppression induced by the chronic disease. Conclusive evidence of the association of microorganisms with chronic diseases requires using epidemiological techniques and molecular tools and teamwork between researchers.