Classification Domain- Eubacteria Phylum- Proteobacteria Class- Gammaproteobacteria Order- Enterobacteriales Family- Enterobacteriaceae Genus- Escherichia Species- E. Coli 0157:H7 - E. Coli 0157:H7 is currently under International Statistical Classification of Diseases and Related Health Problems 10th Revision for “Certain Infectious and parasitic diseases”
Shape & Structure E. Coli 0157: H7 is a serotype of E. Coli, or strain. It is an enterohemorrhagic strain, meaning it causes bloody diarrhea and inflammation of the colon. Gram- Negative, Unicellular, Bacillus (rod shaped) bacteria. May have pili that allow it move and attach to human cells. 0157:H7 refers to the Cell wall antigen number (O), and the H refers to the flagella antigen. Contains divergent plasmids from a common ancestor.
Mode of Nutrition & Effect of Oxygen E. Coli 0157: h7 is heterotrophic and cannot make its own food. E. Coli 0157: H7 are facultative anaerobes that can survive with or without oxygen, which makes them even more dangerous.
Transmission E. Coli 0157: h7 can infect people through contaminated food and water, or oral contact with contaminated surfaces. It is very virulent with a very low infectious dose. They are found on cattle farms and can be present in healthy cattle. The toxins in E. Coli 0157: h7 are highly specific in their receptors, so some animals can carry the bacteria and be unharmed.
Toxins E. Coli 0157: h7 contain “shiga-like” toxins, iron regulated toxins that catalytically inactivate 60S ribosomal subunits of eukaryotic cells, blocking mRNA translation and causing cells to die. Only certain strains of E. Coli carry this quality (mutation with a prophage).
Signs & Symptoms E. Coli infection can cause violent diarrhea and abdominal cramps. It can also be asymptomatic at times. In young children and elderly people, it can cause kidney failure and the destruction of red blood cells.
Diagnosis Sample of the infection fermenting on agar plate is one way used to diagnose someone with E. Coli 0157: h7 Another way is used through stool culture, or detecting the bacteria through the inspection of fecal matter.
Treatment Most people recover from E. Coli 0157: h7 in 5- 10 days without an antibiotic or special treatment. If found in children or elderly, kidney failure can require blood transfusions and kidney dialysis.
Misc. The pathogen results in an estimated 2,100 hospitalizations annually in the United States. Illness is often misdiagnosed. Beef processing is the common point of contamination; during the slaughtering process. E. coli O157:H7 infection is nationally reportable in the USA and Great Britain, and is reportable in most states.