Escherichia coli O104:H4


Escherichia coli O104:H4 is an enteroaggregative Escherichia coli strain of the bacterium Escherichia coli, and the cause of the 2011 Escherichia coli O104:H4 outbreak.[1] The "O" in the serological classification identifies the cell wall lipopolysaccharide antigen, and the "H" identifies the flagella antigen.

Escherichia coli O104:H4
Scientific classificationEdit this classification
Domain: Bacteria
Phylum: Pseudomonadota
Class: Gammaproteobacteria
Order: Enterobacterales
Family: Enterobacteriaceae
Genus: Escherichia
Species: E. coli
Strain: E. c.  O104:H4
Trionomial name
Escherichia coli O104:H4

Analysis of genomic sequences obtained by BGI Shenzhen shows that the O104:H4 outbreak strain is an enteroaggregative E. coli (EAEC or EAggEC) type that has acquired Shiga toxin genes, presumably by horizontal gene transfer.[2][3][4]

Genome assembly and copy-number analysis both confirmed that two copies of the Shiga toxin stx2 prophage gene cluster are a distinctive characteristic of the genome of the O104:H4 outbreak strain.[5][6] The O104:H4 strain is characterized by these genetic markers:[6][7]

  • Shiga toxin stx2 positive
  • tellurite resistance gene cluster positive
  • intimin adherence gene negative
  • β-lactamases ampC, ampD, ampE, ampG, ampH are present.

The European Commission (EC) integrated approach to food safety[8] defines a case of Shiga-like toxin-producing E. coli (STEC) diarrhea caused by O104:H4 by an acute onset of diarrhea or bloody diarrhea together with the detection of the Shiga toxin 2 (Stx2) or the Shiga gene stx2.[9]

Prior to the 2011 outbreak, only one case identified as O104:H4 had been observed, in a woman in South Korea in 2005.[10]

Pathophysiology

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E. coli O104 is a Shiga toxin–producing E. coli (STEC). The toxins cause illness and the associated symptoms by sticking to the intestinal cells and aggravating the cells along the intestinal wall.[11][12] This, in turn, can cause bloody stools to occur. Another effect from this bacterial infection is hemolytic uremic syndrome (HUS), which is a condition characterized by destruction of red blood cells, that over a long period of time can cause kidney failure.[13] Some common symptoms of HUS are vomiting, bloody diarrhea, and blood in the urine.[12]

Infection

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A common mode of E. coli O104:H4 infection involves ingestion of fecally contaminated food; the disease can thus be considered a foodborne illness. Most recently in 2011, an outbreak of the O104:H4 strain in Germany caused the deaths of several people, and hundreds were hospitalised.[14][15][12] German authorities traced the infection back to fenugreek sprouts grown from contaminated seeds imported from Egypt, but these results are debated.[citation needed]

Diagnosis

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To diagnose infection with STEC, a patient's stool (feces) can be tested in a laboratory for the presence of Shiga toxin. Testing methods used include direct detection of the toxin by immunoassay, or detection of the stx2 gene or other virulence-factor genes by PCR. If infection with STEC is confirmed, the E. coli strain may be serotyped to determine whether O104:H4 is present.[11]

Treatment

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E. coli O104:H4 is difficult to treat as it is resistant to many antibiotics, although it is susceptible to carbapenems.[14]

Prevention

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Spread of E. coli is prevented simply by thorough hand-washing with soap, washing and hygienically preparing food, and properly heating/cooking food, so the bacteria are destroyed.[16]

References

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  1. ^ Mellman, Alexander; Harmsen, D; Cummings, CA; et al. (July 20, 2011). "Prospective genomic characterization of the German enterohemorrhagic Escherichia coli O104:H4 outbreak by rapid next generation sequencing technology". PLoS One. 6 (7): e22751. Bibcode:2011PLoSO...622751M. doi:10.1371/journal.pone.0022751. PMC 3140518. PMID 21799941.
  2. ^ "BGI Sequences Genome of the Deadly E. coli in Germany and Reveals New Super-Toxic Strain". BGI. 2011-06-02. Archived from the original on 2011-06-06. Retrieved 2011-06-02.
  3. ^ David Tribe (2011-06-02). "BGI Sequencing news: German EHEC strain is a chimera created by horizontal gene transfer". Biology Fortified. Archived from the original on 2012-05-27. Retrieved 2011-06-02.
  4. ^ Maev Kennedy and agencies (2011-06-02). "E. coli outbreak: WHO says bacterium is a new strain". London: guardian.co.uk. Retrieved 2011-06-04.
  5. ^ "BGI releases the complete map of the Germany E. coli O104 genome and attributed the strain as a category of Shiga toxin-producing enteroaggregative Escherichia coli (STpEAEC)". BGI. 2011-06-16. Retrieved 2011-06-20.
  6. ^ a b "Copy number analysis of German outbreak strain E. coli EHEC O104:H4". Johannes Kepler University of Linz. 2011-06-11. Retrieved 2011-06-15.
  7. ^ "Characterization of EHEC O104:H4" (PDF). Robert Koch Institute. 2011-06-03. Archived from the original (PDF) on 2012-03-25. Retrieved 2011-06-15.
  8. ^ "The EU integrated approach to food safety".
  9. ^ "Case Definition for diarrhoea and haemolytic uremic syndrome caused by O104:H4" (PDF). European Commission. 2011-06-03. Retrieved 2011-06-16.
  10. ^ Bae, WK; Lee, YK; Cho, MS; et al. (June 30, 2006). "A case of haemolytic uremic syndrome caused by Escherichia coli O104:H4". Yonsei Medical Journal. 47 (3): 473–479. doi:10.3349/ymj.2006.47.3.437. PMC 2688167. PMID 16807997.
  11. ^ a b Frank, C; Werber, D; Cramer, JP; et al. (October 26, 2011). "Epidemic profile of Shiga-toxin–producing Escherichia coli O104:H4 outbreak in Germany". New England Journal of Medicine. 365 (19): 1771–1780. doi:10.1056/NEJMoa1106483. PMID 21696328. S2CID 205093464.<http://www.nejm.org/doi/full/10.1056/NEJMoa1106483>
  12. ^ a b c Reinberg, Steven. "German E. Coli Strain Especially Lethal - Infectious Diseases: Causes, Types, Prevention, Treatment and Facts on MedicineNet.com." Medicinenet.com. MedicineNet Inc, 22 June 2011. Web. 08 Nov. 2011. <http://www.medicinenet.com/script/main/art.asp?articlekey=146119 Archived 2012-01-18 at the Wayback Machine>.
  13. ^ European Food Safety Authority. "Shiga Toxin-producing E. Coli (STEC) O104:H4 2011 Outbreaks in Europe:." EFSA Journal. European Food Safety Authority, 3 Nov. 2011. Web. 08 Nov. 2011. <http://www.efsa.europa.eu/en/efsajournal/pub/2390>.
  14. ^ a b Gorman, Christine. "E. Coli on the March: Scientific American." Science News, Articles and Information | Scientific American. Scientific American, 7 Aug. 2011. Web. 08 Nov. 2011. <http://www.scientificamerican.com/article.cfm?id=e-coli-on-the-march>.
  15. ^ "July 8, 2011: Outbreak of Shiga Toxin-producing E. Coli O104 (STEC O104:H4) Infections Associated with Travel to Germany | E. Coli." Centers for Disease Control and Prevention. Center for Disease Control and Prevention, 8 July 2011. Web. 08 Nov. 2011. <https://www.cdc.gov/ecoli/2011/ecolio104/>.
  16. ^ "CDC - Escherichia coli O157:H7, General Information - NCZVED." Centers for Disease Control and Prevention. Centers for Disease Control and Prevention, 8 July 201. Web. 08 Nov. 2011.