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E. coli: The Good, The Bad, And The Ugly. Introduction. How many of you like to go swimming in Lake Shafer?. How many of you live in the “watershed area”?. Hoagland Ditch Watershed. Honey Creek Watershed. What is a watershed?. It is the area drained by a water system. 0.001 mm.
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E. coli: The Good, The Bad, And The Ugly
Introduction How many of you like to go swimming in Lake Shafer? How many of you live in the “watershed area”?
Hoagland Ditch Watershed Honey Creek Watershed What is a watershed? It is the area drained by a water system.
0.001 mm What is Escherichia Coli? E. coli was discovered by Dr. Theodor Escherich, who discovered this bacterium in 1885. It belongs to the Family Enterobacteriaceae. From Greek wordenterikos(intestines) These organisms happily inhabit the intestinal tract of most warm blooded animals. 10 μm
E. coli & Lake Shafer Lake Shafer is known to contain high levels of E. coli periodically during the year. Sources of water and E. coli draining into Lake Shafer comes from the watershed area. 81% of ditches, rivers, and lakes do not support full body contact recreation in Indiana (IDEM)
E. coli Factoids E. coli colonizes the bowel of the average human fetus within 40 hours of birth. In newborn infants, most of the bacteria present are E. coli. There are approximately 107 (10,000,000) E. coli bacteria per 1 gram of an adult human’s intestine. Only 0.1% of the total bacteria in the adult human intestine are E. coli.
Escherichia coli (E. coli) Can be used to indicate the possible presence of bacteria that may be harmful to human health. Other indicators of water quality test for things like sediment and fertilizers. 0.001 mm BASIC RULE: If the water looks dirty, it probably is!!!
What Good Are E. coli? • Protects the intestinal tract from bacterial infections • Aids in digestion • Produces our main source of vitamins B12 and K 4) Lives symbiotically with us (we help them to live, and they help us to live)
Hmmmmm Who doesn’t wantANYbacteria or E. coli in them? Animals born and raised “germ free” are really wimpy . . . They have thin intestinal walls, puny heart output, and require lots of vitamin supplements just to stay alive.
Bad E. coli While most E. coli are good for you, there are a few strains of E. coli that are harmful to humans. ~ 5 billion bacteria in your intestines alone It is possible to get an individual strain of E. coli that is harmful to you.
Most notorious strain of bad E. coli Produces a powerful toxin and can cause severe illness Most dangerous for little kids, the elderly, and the sick Damages the intestines, causes bloody diarrhea, and other complications E. coli O157:H7 0.001 mm 0.001 mm
According to USDA, E. coli O157:H7 causes ~ 73,000 cases of infection and 61 deaths in the USA each year. Many countries around the world are constantly suffering from E. coli contamination. Common cause of diarrhea in tourists Local, National, & International Concern
Attendees of a county fair became ill from E. coli poisoning Source: Runoff from a barn that housed cattle contaminated the water supply at the fair At least 155 people became ill Case Study: New York 1999
A toddler’s swimming pool was contaminated with E. coli Several children were hospitalized Chlorine from pools does kill bacteria, but it takes time Case Study: Georgia 1998
Undercooked meat Unpasteurized milk, apple juice, and orange juice Swimming in or drinking water contaminated with sewage Main Sources of E. coli
Bacteria in the diarrhea of infected persons can be passed on if their hands are not washed well Unwashed vegetables and fruits Main Sources of E. coli Most sources CAN be avoided!!!
Lake Shafer contains high amounts of E. coli during different times of the year. Chances of getting sick from E. coli are very small Currently, research is being done to try and solve the problem. What does this have to do with us? But we want to make them even smaller!
Indiana water-quality standard for full-body contact is 235 cfu/100mL Less money is made at Indiana Beach People blame one another for the problem More information needed to find cheap solutions that will work E. coli in Lake Shafer E. coli concentrations up to20,000colony-forming units (cfu) per 100mL
Theory: Any idea, based on scientific fact, to explain something. Hypothesis: An idea to account for certain facts, and it may be tested to see whether or not it is correct The Scientific Method
1) Know what possible sources are: Farm Animals Fertilizers Sewage Treatment Plants Residential Areas (septic tanks) 2) Some of these sources get into the water system Where’s It All Coming From?
Method: A procedure or way of doing something Results: Interpretation of the data produced by the method used to test the hypothesis Conclusion: Summarizes briefly the hypothesis and the results to produce an ending to your experiment The Scientific Method
Upstream: The directionfromwhich the stream flows Downstream: The directiontowhich the stream flows Definitions Upstream Downstream Flow
flow Sampling Strategy (Methods)
Place water sample on medium in petri dish. Wait 24 – 48 hours to allow E. coli to grow Count colonies of E. coli in the petri dish Each dot represents an entire colony of E. coli, not an individual E. coli cell Collecting & Analyzing Data
Results & Conclusions E. coli count units = cfu/100ml
Results & Conclusions E. coli count units = cfu/100ml