Amidst the many angering and gut-wrenching aspects of the Hurricane Katrina aftermath, lies a pronounced lack of information. How many people have died so far? Who exactly is the person in charge of relief efforts? How will relief moneys be distributed to those in need? These topics, and others, seem suspiciously absent in the coverage of this enormous natural disaster. Granted, this is not just the media's problem because the information might not exist, a further symptom of the laggard pace of the overall response.

So when reports start to surface that the flood waters in New Orleans are contaminated with dangerously high levels of chemicals and bacteria, it's not surprising that it's difficult to find background information in the reports. When you say the word "E. coli" to an average person, he no doubt thinks of his kitchen cleaner and the red crossed-out circle that covers this word during the product's commercial. Most know that E. coli is an illness causing bacteria, but that is where the knowledge ends. A further background on an organism like E. coli is warranted not because it will disprove the fears of EPA officials about stagnant floodwaters, but just to attempt to add more information in a time that lacks it.

By and large, Escherichia coli is actually quite a close companion of yours and mine. The bacterium is enteric to every human body, living in your large intestine by the trillions. In fact, there are so many E. coli in your body that the average person excretes over 10^11 per day! Still, the bacterium only represents 0.1% of the total bacteria in our digestive tracts. We generally have a healthy symbiotic relationship with these critters--they help us digest our food in exchange for a perfect living environment. Its important to note, however, that these bacteria are really living on the outside of our bodies (your whole digestive system is just a long tube that runs from your mouth to your anus, and is not really "inside" your body at all.)

E. coli get some of its bum rap from the rogue strains that exist only to cause trouble. At some point in the history of the bacteria, certain genetic alterations occurred that created varieties that produce specific toxins. One such famous strain is 0157:H7, known mostly for contaminating meats and some other foods. Mr. H7's specialty is secreting Shiga-like toxin, a protein that causes damage to intestinal epithelium, leading to bleeding and fluid loss. Infection with this strain can be deadly, especially for the young and elderly.

Every person has their own little (well, I guess not so little) family of E. coli helping around the intestine, but problems also arise when one person comes into contact with another's family. This can happen through only one way, and that way involves the word feces. When you have a flooded city with a high quantity of sewage, there is a strong possibility of this type of E. coli contact. Such exposure is usually reffered to as Diarrheagenic E. coli, and the symptoms are summed up in the name. Although not as dangerous as the reaction to Shiga-like toxin, such infections still pose the most danger to those humans at the age extremes.

No matter what, there's always more to say than space to say it. Is it fair to ask that all reports mentioning the EPA's determination that the New Orleans flood waters contain 10 times the safe level of E. coli also give a background on this organism? Not really. However, it does seem like the best way to inform about a science is to do so when it is relevant.

« Previous Next »