MIDRP Overview History & Achievements Current Research Efforts External Programs

Program Overview:
Diarrheal diseases have had a major impact on military operations throughout recorded history. During World War II, rates of diarrhea or dysentery in troops operating in North Africa were 497 cases per 1000 men over the course of the Battle of Alamein, tipping this famous battle in favor of the English Army. During Operation Desert Shield/Desert Storm half a million troops were rapidly mobilized to the Saudi Arabian peninsula, outstripping quartermaster capacity to provide safe sources of food and water. After an average of two months in Saudi Arabia, 57 percent of the surveyed troops had at least one episode of diarrhea, and 20 percent reported that they were temporarily unable to carry out their duties because of diarrheal symptoms. Epidemiologic data has indicated that enterotoxigenic E. coli (ETEC), Campylobacter jejuni, and Shigella spp. (particularly S. flexneri and S. sonnei) are the most common causes of diarrheal disease in deployed personnel. Therefore, the program goals are centrally focused on development of safe and effective vaccines that confer broad coverage against each of these pathogens.

Vaccine to Prevent Diarrhea Caused by Campylobacter: Campylobacter jejuni is a leading cause of diarrheal disease worldwide and a documented threat to US military personnel. Campylobacter enteritis presents with diarrhea, fever, abdominal cramps, aching joints and muscles and occasionally bloody diarrhea. Deployed Department of Defense (DoD) personnel that develop Campylobacter enteritis are ill for an average of four days, even with optimal antibiotic therapy, ninety-four percent report a marked decrease (47 percent), or complete inability (47 percent) to perform their mission. Little is understood about the mechanisms by which it causes disease. Thus, the Program Area has continued to focus on understanding the mechanisms of Campylobacter pathogenesis and immunity. This Task is seeking to develop a subunit campylobacter vaccine to prevent diarrhea in deployed forces.

Vaccine to Prevent Diarrhea Caused by ETEC: Enterotoxigenic Escherichia coli (ETEC) are a leading cause of diarrhea in both military and civilian travelers to the tropics and subtropics, accounting for 25-50 percent of disease episodes in most settings. It has also been recognized that ETEC diarrhea is a foremost public health problem for infants in developing countries, accounting for an estimated 631 million diarrheal episodes and some 800,000 deaths annually. ETEC cause acute secretory diarrhea, the adverse consequences of which are dehydration, temporary incapacitation and death in the very young. Manifestations of disease are exacerbated in heat-stress environments and hot climates. This Task seeks to develop a vaccine to prevent ETEC diarrhea by targeting the organism's colonization factors and a specific enterotoxin that stimulates intestinal fluid.

Vaccine to Prevent Diarrhea Caused by Shigella: Shigella is a leading cause of diarrhea in the U.S. military. The symptoms and effects of shigellosis are similar to that of ETEC and Campylobacter. The objective of this Task is to develop a vaccine that will prevent diarrhea caused by Shigella spp. This effort will examine two vaccine strategies. The first strategy will use a S. flexneri subunit vaccine delivered by an intranasal or other route. The second strategy will use a live attenuated strain of S. flexneri administered orally to induce protection.

Diarrhea Prevention | Rickettsial Disease | Wound Infection Research