Enterotoxigenic Escherichia coli

Enterotoxigenic "Escherichia Coli" (ETEC) is a type of "Escherichia coli" and the leading bacterial cause of diarrhea in the developing world, as well as the most common cause of Traveler's diarrhea. [http://www.who.int/vaccine_research/diseases/diarrhoeal/en/index4.html World Health Organization. Enterotoxigenic "Escherichia coli" (ETEC).] ] Each year, approximately 210 million cases and 380,000 deaths occur, mostly in children, from ETEC. [ [http://www.who.int/vaccine_research/diseases/e_e_coli/en/ World Health Organization. Institute for Vaccine Research. Enterotoxigenic "escherichia coli" (ETEC).] ] A number of pathogenic isolates are termed ETEC, but the main hallmarks of this type of bacteria are expression of one or more enterotoxins and presence of fimbriae used for attachment to host intestinal cells. Enterotoxins produced by ETEC include heat-labile (LT) enterotoxin and heat-stable (ST) enterotoxin. [ [http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pubmed&pubmedid=16020685 Qadri F, Svennerholm AM, Faruque ASG, Bradley Sack R. Enterotoxigenic "Escherichia coli" in Developing Countries: Epidemiology, Microbiology, Clinical Features, Treatment, and Prevention. "Clinical Microbiology Reviews". 2005; 18(3):465–483.] ] LT is similar to cholera toxin; it increases the level of cAMP in intestinal cells, and this causes an increase in electrolyte and water excretion (diarrhea). ST stimulates production of cGMP, also leading to increased fluid excretion and diarrhea. Because enterotoxic "E. coli" strains are non-invasive, they do not cause inflammation or bloody diarrhea. Infection with ETEC can cause profuse watery diarrhea and abdominal cramping. Fever, nausea with or without vomiting, chills, loss of appetite, headache, muscle aches and bloating can also occur but are less common. [http://www.cdc.gov/ncidod/dbmd/diseaseinfo/etec_g.htm US Centers for Disease Control and Prevention. Enterotoxigenic "Escherichia coli" (ETEC)] ]

Prevention and treatment

The most effective method of preventing diarrhea due to ETEC is vaccination. However, vaccines against ETEC are not yet available for populations where ETEC is endemic. There are currently available treatment options against traveler's diarrhea, specifically against illness due to cholera. Data from natural history studies of ETEC infections in children in developing countries suggest that immunization against ETEC early in life may be an effective preventive strategy. [ [http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6TD4-4HCN99R-2&_user=5502795&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_acct=C000067590&_version=1&_urlVersion=0&_userid=5502795&md5=c0d1e587f23f69dd5d5011aefc8d2244 Girard M, Steele D, Chaignat CL, Kieny MP. A review of vaccine research and development: human enteric infections. "Vaccine". 2006; 24:2732–2750] ] The World Health Organization recommends further research into the development of a vaccine against ETEC. Treatment for ETEC infection includes rehydration therapy and antibiotics, although ETEC is frequently resistent to common antibiotics.

ee also

*Diarrhea
*Diarrheal diseases
*Infectious diarrhea
*Traveler's diarrhea
*Gastroenteritis

References