Water, like everything else on Earth, including you, is full of bacteria. But not all bacteria are created equal, with many being more harmful than others. Yes, Escherichia coli (E. coli) pollutes our ground and surface water through fecal contamination, but the bacteria is also simply found and widely distributed in nature. As one of our hosts, Christian, bid adieu to us, his last pathogen of choice is E. coli. Listen in as the bacteria-loving buds discuss strains and characteristics, causes, effects, and environments of this curious bug. More about E. coli: CDC’s summary of E. coli What is E. coli O157:H7? Coliform Bacteria in Drinking Water Supplies Stay tuned for more episodes, posting on the first Thursday of each month. Subscribe to our show wherever you get your podcasts and find more info at weebeastiespodcast.com The Wee Beasties podcast is a production of Nephros, Inc., a company committed to improving the human relationship with water through leading, accessible technology *** SHOW TRANSCRIPT: Christian: Kimothy… Kimothy: Christian… Christian: Happy New Year. What a year it has been, eh? Kimothy: Happy New Year, Christian. Yeah, what a great year. And a big year ahead – lots of changes. Including for you – this is your last podcast today, right? Christian: Yeah, that’s correct. Really sad to have to move on – I think this is such an important forum to have these conversations, and I will miss the opportunity to share microbiology with our audience. Kimothy: Well, what do you think our Swan Song should be for your last episode? Christian: I thought E. coli might be a good one to end on. A well-known, and often misunderstood, waterborne pathogen. Kimothy: Yeah, no doubt, Christian. Christian: So, when I think of E. coli, I immediately go to headlines about spinach recalls and announcements about contaminated meat at restaurants. But E. coli bacteria can just as easily contaminate a municipal water supply, right? And E. coli is a gut bacterium, so when something is contaminated, are we just saying that it has gut bacteria or, really, just poop in the water? Help me understand this, is water contaminated with E. coli, just water that has fecal matter in it? Kimothy: [laughs] Well, yes, essentially. But, let’s back up for a moment and outline a few things. So, E. coli is a bacterium that lives in the intestines of warm-blooded animals, and most strains of E. coli bacteria are not harmful and are an essential part of the gut flora for healthy digestion. That said, there are several pathogenic strains, the most common one in the U.S. being a Shiga toxin-producing E. coli called, O157:H7. Now, all E. coli is part of a group I mentioned during our last episode, called coliforms. Coliforms are a kind of rod-shaped bacteria that are found in soil, plants, and intestinal tracts of animals – in this group you have total coliforms and fecal coliforms. The most prevalent fecal coliform species is E. coli. And the most dangerous fecal coliform is E. coli O157:H7, so to get back to your question. Yes, it’s poopy water. Christian: Ahh, I knew it. So that’s the scoop on poop? Kimothy: Well, the gut microbiome has a lot more to it than that, but that’s the scoop on E. coli in water. Christian: Okay, okay…so, a couple of things at which I’d like to take a closer look. I got that if water has E. coli in it, it is because the water has been contaminated with fecal matter, but you mentioned Shiga toxin E. coli and coliforms. What is Shiga toxin and why do we care about coliforms? I mean, I don’t want coliforms in my drinking water, but you’ve mentioned coliforms in two episodes now, so I just wanted to pause and ask a little more. What’s the importance here? Kimothy: Sure, Christian. So, coliforms, as I mentioned encompasses a group of rod-shaped bacteria, and the reason they’re important is, first, they always exist in the digestive tracts of animals and their waste; and second, they are a great ‘indicator’ organism. That is, you can test for coliforms as a diagnostic tool that can give you a read on the probability of other pathogenic organisms being present in your sample. If you conduct a coliform test and it’s positive, you know on a list of probable outcomes, that there is some risk of contracting a waterborne illness or disease. Okay, now for the Shiga toxin: The E. coli that produce Shiga toxin are called Shiga toxin-producing E. coli or STEC for short. The most common type of STEC is O157:H7 and has emerged as one of the most serious causes of severe human gastrointestinal disease. Now, the pathogenesis involves the E. coli bacterium releasing the Shiga toxin in the gut of a human which attacks and destroys the lining of the intestinal tract, resulting in bloody diarrhea. According to the CDC, there are about 70,000 cases of hospitalization from O157:H7 every year in the US. Christian:...
