Bad Bug Book:
Foodborne Pathogenic Microorganisms and Natural Toxins Handbook
Enteroinvasive Escherichia coli
Enteroinvasive Escherichia coli or (EIEC)
Currently, there are four recognized classes of enterovirulent E. coli (collectively referred to as the EEC group) that cause gastroenteritis in humans. E. coli is part of the normal intestinal flora of humans and other primates. A minority of E. coli strains are capable of causing human illness by several different mechanisms. Among these are the enteroinvasive (EIEC) strains. It is unknown what foods may harbor these pathogenic enteroinvasive (EIEC) strains responsible for a form of bacillary dysentery.
Enteroinvasive E. coli (EIEC) may produce an illness known as bacillary dysentery. The EIEC strains responsible for this syndrome are closely related to Shigella spp.
Following the ingestion of EIEC, the organisms invade the epithelial cells of the intestine, resulting in a mild form of dysentery, often mistaken for dysentery caused by Shigella species. The illness is characterized by the appearance of blood and mucus in the stools of infected individuals.
Infective dose -- The infectious dose of EIEC is thought to be as few as 10 organisms (same as Shigella).
The culturing of the organism from the stools of infected individuals and the demonstration of invasiveness of isolates in tissue culture or in a suitable animal model is necessary to diagnose dysentery caused by this organism.
More recently, genetic probes for the invasiveness genes of both EIEC and Shigella spp. have been developed.
It is currently unknown what foods may harbor EIEC, but any food contaminated with human feces from an ill individual, either directly or via contaminated water, could cause disease in others. Outbreaks have been associated with hamburger meat and unpasteurized milk.
One major foodborne outbreak attributed to enteroinvasive E. coli in the U.S. occurred in 1973. It was due to the consumption of imported cheese from France. The disease caused by EIEC is uncommon, but it may be confused with shigellosis and its prevalence may be underestimated.
Dysentery caused by EIEC usually occurs within 12 to 72 hours following the ingestion of contaminated food. The illness is characterized by abdominal cramps, diarrhea, vomiting, fever, chills, and a generalized malaise. Dysentery caused by this organism is generally self-limiting with no known complications. A common sequelus associated with infection, especially in pediatric cases, is hemolytic uremic syndrome (HUS).
All people are subject to infection by this organism.
Foods are examined as are stool cultures. Detection of this organism in foods is extremely difficult because undetectable levels may cause illness. It is estimated that the ingestion of as few as 10 organisms may result in dysentery.
For more information on recent outbreaks see the Morbidity and Mortality Weekly Reports from CDC.