The epidemiology, detection and control ofEscherichia coli O157

Abstract

Numbers of cases of human infections caused by Escherichia coli O157 have increased over the last decade in many countries. As well as the typical symptoms of gastrointestinal illness, the organism can cause more life‐threatening diseases such as haemorrhagic colitis and haemolytic uraemic syndrome (HUS). Although the incidence remains relatively low compared with the other foodborne pathogens such as Campylobacter and Salmonella, the mortality rate associated with infection is much higher. Cattle are thought to be the main environmental source of this organism, and most cases have been associated with consumption of beef and beef products. However, other food vehicles have been identified, such as apple cider and raw or unpasteurised milk and milk products. Cross‐contamination has been shown to be an important factor in outbreaks, which, together with the fact that the infectious dose is low (as few as 10 cells), means that robust hygienic procedures are essential at all stages of the food chain to reduce risk of infection. Person‐to‐person spread is a common source of illness, and several laboratory‐acquired cases have also occurred. Efficient detection, isolation and confirmation techniques are required to establish the reservoirs of this organism in the environment and its spread into, and within, the food chain. This article reviews the epidemiology of E coli O157 and discusses detection and preventative methods, both developed and developing. © 1999 Society of Chemical Industry

Occurrence of Intestinal and Extraintestinal Virulence Genes in Escherichia coli Isolates from Rainwater Tanks in Southeast Queensland, Australia

“…However, none of the isolates was positive for the stx 1 , stx 2 , and hlyA genes. E. coli O157:H7 is known to harbor stx 1 , stx 2 , or both toxin genes along with the eaeA gene (9,37,43). All eaeA-positive strains were further tested for the presence of the bfpA (bundle-forming pilus) gene, which indicates whether the strains are EPEC or not (25).…”

A rapid bioassay for single bacterial cell quantitation using bioconjugated nanoparticles

“…The analysis of bacteria is vital for food safety, clinical diagnosis and therapies, portable water, and prevention strategies to combat bioterrorism agents. Escherichia coli O157:H7 is one of the most dangerous agents of food-borne diseases (1). Several of the reported outbreaks of E. coli O157:H7 have led to death, especially in cases involving children and the elderly (2)(3)(4)(5).…”

“…Several of the reported outbreaks of E. coli O157:H7 have led to death, especially in cases involving children and the elderly (2)(3)(4)(5). Given the low infectious dose of E. coli O157:H7 (Ϸ10-100 cells), the presence of even a single bacterium in food may pose a serious health risk (1,6). Therefore, a simple, rapid, and sensitive detection of trace amounts of E. coli O157:H7 and other bacterial pathogens is critical for minimizing or eliminating potential infections.…”

“…Therefore, a simple, rapid, and sensitive detection of trace amounts of E. coli O157:H7 and other bacterial pathogens is critical for minimizing or eliminating potential infections. Traditional methods for the detection of trace amounts of bacteria require amplification or enrichment of the target bacteria in the sample (1,7,8). These methods tend to be laborious and time-consuming because of the complicated assay procedures (9)(10)(11)(12)(13)(14)(15)(16)(17)(18).…”

Slugs: Potential Novel Vectors of Escherichia coli O157

“…The incidence of human disease is relatively low in industrialized countries compared to other enteric pathogens such as Campylobacter and Salmonella spp. (4,25,35). However, the sequelae can be severe, with approximately 5 to 10% of patients exhibiting hemolytic-uremic syndrome with a mortality rate of 3 to 5% (28,48).…”