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What is E. Coli? E. Coli is normal flora in the human intestinal tract, certain strains
carry genes for virulernce factors which are not present in the normal E. Coli cell.
These virulence factors allow the bacterium to produce toxins, and to have enhanced
adherence to the host’s cells. The infectious dose has also been shown to be amazingly
small for these strains ( it only takes 10 bacteria to cause infection with some strains). So far, the main documented source of Enterohemorragic E. Coli is from undercooked hamburger meat, although in one case the source was traced back to raw milk. Meat is usually not colonized by bacteria except for the surface which always carries bacteria. But the outside of the meat is usually cooked sufficiently to kill most of the bacteria. However, microscopic punctures and tears from handling the meat allow the bacteria to spread to the inside, where they are less likely to be destroyed by cooking. Recently the Taos Pueblo Environmental Office did testing on the Rio- Pueblo de Taos at different sites for E. Coli bacteria . The Pueblo didn’t find any signs of E. Coli bacteria in the river. The reason for this testing is because the Rio-pueblo runs directly in the middle of the pueblo and is used by tribal members who live inside the pueblo and this is a big concern because the water is used for cooking, drinking, and religious uses. The following is a water analysis recording which was taken at different sites: see attached recording sheet. The following are guidelines of E. Coli too look for: 1)Cause of illness- strain of enteropathic E. Coli. 2) Incubation period: Two to Four days. 3) Symptoms: Hemorrhagic colitis, hemolytic ureic syndrome. 4) Possible Contamination: Ground Beef, raw milk, and chicken. 5) Steps for Prevention: Thoroughly cook meat; avoid cross-contamination.
The following is also a description of the technology: E.Coli are important as indicators of fecal contamination in soils, groundwater, and drinking water. Fecal contamination is the result improperly treated human or agricultural waste, and poses a serious health hazard through drinking water and swimming areas. E. coli is also a serious food pathogen. Tests for total coliform and fecal coliform types have existed for quite some time but do not distinguish between naturally present coliforms and E.coli. Tests based on series of enzymatic reactions are prohibitively expensive for high volume applications. Dr. Art Ley, at the Ontario Ministry of Environment and Energy, and Dr. Ray Bowers at Queens University have combined their efforts to develop a compound, Indoxyl-a- D-Glucuronide (IBDG) which is a specific chromogen for E. coli. E.coli are one of a few bacteria with Glucuronidase enzyme activity, and can cleave IBDG to release an insoluble chromogen. When E.coli are cultured on an agar medium containing IBDG the resultant colonies are stained indigo blue. In presence of other bacteria, these blue colonies stand out and E.coli can easily be enumerated. There is also another technique called Genetic-fingerprinting which helps identify E.coli bacteria. Scientists have developed a genetic fingerprinting process that helps public officials detect different strains of the potentially deadly E.coli bacteria. E.coli is a bacterium normally found in all humans, but certain strains such as 0157:h7, carry a toxin. The cutting edge technology is called Pulsed Field Gel Electrophoresis (PFGE), which relies on genetic fingerprinting to determine if different samples of E.coli are related. E.coli bacteria from victims of an outbreak are cultured to increase their numbers. The bacteria’s DNA is chemically cut into small pieces, which are separated according to size. A fluorescent dye illuminates the DNA under ultraviolet light, allowing scientists to compare different samples. The new technique prove invaluable to public health officials in Georgia last June, helping them trace an E.coli outbreak to a popular water theme park in suburban Atlanta. Using database of E.coli cultures, scientists separated the water park cases from all the other E.coli cases the Georgia Department of Health was dealing with. The Centers for Disease Control (CDC) has since established a database of the genetic fingerprints called Pulsenet, allowing public health officials from across the country to more easily identify and cope with E.coli outbreaks. The CDC reports that the dangerous strain of E.coli known as E.coli 0157 sickens up to 20,000 people in the united states each year and kills several hundred. An instant test for the E.coli bacteria has also been developed by an American researcher. Current tests take about 24 hours as the bacteria have to be incubated before they can be detected. Even the most recent DNA tests for E.coli, which rely on artificially speeding up the spread of the bacteria, need several hours before a result can be obtained. The new test, developed at the Berkeley Lab in California, can instantly detect the presence of E.coli by mimicking its structure and bonding with bacteria, triggering a color change in the sensor. The following are ways on how to investigate water contamination: First by finding out how the water got contaminated with bacteria. Second by looking into flooding for a possible cause due to heavy rainfall which might wash bacteria into streams, and rivers. Always check equipment for malfunctions at water companies if applicable which may contribute to the problem. Always take water samples to check for contamination and if contamination is present you should warn residence if E.coli is present in the drinking water and advise them to boil it before use.
In conclusion I think that all Environmental Departments should always check the water for E.coli contamination. The Taos Pueblo Environmental Office did the right thing by checking the water streams for E. coli and my main concern is the rainbow, cut throat, and German brown trout that are in the Rio-pueblo because people fish in these streams. My other main goal is to check the streams for E.coli as much as possible due to the growing population of our tribe. |