Bryan Essien, Ph.D., Postdoctoral Research Fellow (Merchant laboratory), Department of Internal Medicine, Division of Gastroenterology, University of Michigan Medical School

Salmonella typhimurium is the most common cause of bacterial infections in the GI tract, especially during the summer when people are handling raw foods (eggs, chicken, beef, fruits, and vegetables).  A person infected with this organism will develop abdominal pain, vomiting, and diarrhea.  In most instances, the infection is self-limited, but some will develop a blood infection which can lead to a high fever (“typhoid fever”), that can be fatal.  Asymptomatic carriers of this organism can shed the bacteria. Such shedding the way in which “Typhoid Mary” spread the disease as a domestic cook in the early 1900’s.  The photo is from a study to understand how the colon normally mounts a vigorous defense against infection by the bacteria (yellow in this image) before it reaches the bloodstream.