Bacteria, Beef and the Fascinating Science Behind E. coli

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This is a podcast about one health the idea that the health of humans, animals, plants and the environment that we all share are intrinsically linked.

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Coming to you from the University of Texas Medical Branch in the Galveston National Laboratory.

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This is infectious science.

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We're enthusiasm for science.

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This is contagious.

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Summer wouldn't be summer without a little bit of barbecue.

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But not all barbecue is created equal.

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Take this past March, when 1.7 tons of beef were recalled in the US due to contamination with E coli.

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On this installment of the infectious science summer camp, we're inviting Dr Alfredo Torres, associate provost at UTMB and professor in the Department of Microbiology and Immunology, to help us understand a little bit more about this recall and learn how to stay safe this summer while we're at the grill.

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So when I think about bacteria, e coli is the first thing that comes to my mind, because it's everywhere, it's in our bodies, it's in the environment and it's also a really important cause of disease worldwide.

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In fact, according to the World Health Organization, it's responsible for more than 300 million illnesses and nearly 200,000 deaths worldwide.

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So to talk about this, I'm Danielle and I've got Connie here with me.

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Hello, happy Friday.

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And we also have Dr Torres here.

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Alfredo Torres is a faculty member and a professor here at UTMB, and also an assistant provost.

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Hi, dr Torres, hey how are you doing?

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Good.

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Thanks so much for coming to talk to us about this Kind of recently in the news, 1.7 tons of beef were recalled due to contamination with E coli.

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So he's here to talk to us today about E coli, what it is, how does that contamination happen and why do we care?

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So, dr Torres, how did you first get interested in science?

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Well, I was born in California, but with my family we went back to Mexico when I was five years old.

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Oh, ok.

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So growing up in Mexico I got very interested in infectious diseases.

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Because you see people getting sick, you're sitting at the street the traditional, what they call moctezuma revenge.

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You go there, you eat the tacos at the street and then you got sick.

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So that got my attention and I started studying science in college in Mexico and eventually I found my way to the microbiology lab and since then I got hooked to microbiology and I was interested to figure out how microbes cause disease.

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And that's what I have been doing for the past 20 years here at UTMB and the past 40 years, I think, since I started college.

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Yeah, so can you think of any key moments that you just knew that this is, this is what you wanted to do, or any key early inspirations?

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Yeah, I think one of the things my career, my major, is chemistry, pharmacology, biology.

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You might think what is that?

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What is that?

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And pieces of everything, but mainly in Mexico.

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These people that get this degree normally work in clinical laboratories and they do clinical analysis.

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So I have an uncle that also has the same major and he has his lab in Mexico and he took me when I was 12, 13 years old to go there and start learning and look through the microscope and figure out what was happening and literally I recall that I was the first hook to see cells and potentially get bacteria and see how they were acting, although it was a clinical lab and we were just diagnosing.

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That was the yeah, that kind of like special really interesting experience.

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Yeah, I kind of had something really similar when I was in high school.

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I got to hang out in a microbiology lab and back when I was in high school all the girls had these trapper keepers with clear covers and they would put pictures of movie stars and like their friends in them and I got to take a picture of the bacteria we were looking at in the lab and I filled my trapper.

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Oh, that's super cool.

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That's super cool.

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I was a little bit nerdy, but also really proud at the same time.

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So I can definitely relate how those early introductions can really impact you for the rest of your career.

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So you went to school, were you a good?

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student?

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I think so that was you're going to call it nerd?

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Yes, I was a nerd.

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Yeah, and how was it managing kind of that journey and balancing your professional and your nerdy self with your regular, like personal life?

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Well, one of the things that happens to me when I was in Mexico I was always kind of the outsider, so I was not born there.

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I came when I was a kid but I always felt that my place was not there, so it was not an introvert, but I was not a really an extrovert.

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And one of the things that helped me and I really really think being a boy scout I became a boy scout that helped me to learn some leadership skills and being outside in the field with other kids that were nerdy like me and enjoying things that I was doing like me, that was an eye opening for me.

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That part definitely changed how I approach things and approach life and how completely changed the way I am now, Because you had me as a professor.

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I don't think you know this, that I'm an introvert.

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No, I would never called you an introvert.

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Yeah, so now I was able to change completely.

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Yeah, you know the way I am.

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Oh, that's so interesting, how that kind of early experience affected you.

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So you went to grad school in Mexico or in the US.

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So the story goes like this.

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So I finished college in Mexico and people had asked me this question why do you decide to become a PhD, a doctor in sciences?

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And I don't have an answer.

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I always was in college and I would say I want to finish as soon as possible because I want to go back to the United States and get a PhD.

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Oh, okay, I don't know where this came from and that was the mission.

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Yeah, even my wife my wife was my classmate.

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She remembers.

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I say like everybody hates you because you hate to skip classes, you hate when they cancel exams because you wanted to finish and then you want to move on and do that.

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So as soon as I finished college, I enrolled in a master degree in Mexico.

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At the time I didn't have money to travel or anything, so I was very poor.

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I was working as a high school professor and then doing part-time master degree in microbiology.

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I think in my second year in the master's program I met a professor that came to give a talk to my university.

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I was parking in Mexico Pueblo in central Mexico, and I don't know how he found out that I was an American that always wanted to come back.

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So he came talk to me and say Alfredo, you're interested to do research and do your master thesis, potentially in the United States.

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And I say absolutely yeah.

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So he came back.

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He used to work in Dallas and then at the time there was no email or anything.

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So he sent me a letter and he said I want you in the lab, I want to see you here in a month.

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So literally I dropped everything, I grabbed my bags and then I took a bus for 18 hours or whatever, so many hours from Puebla to all the way to Dallas and I show up and I start working in his lab in doing research.

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And what did your wife say?

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Was she your wife?

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No, my wife was my.

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My wife was my girlfriend at the time.

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Yeah.

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And she said well, it's what you really want to do.

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Yeah, Good luck.

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And hopefully we'll see each other again.

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Then she became my wife.

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Yeah, that's the story.

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But, yeah, I came and I was doing a master's degree and then, as you and everybody working in science, you know that sometimes we have money to do research, sometimes we don't, right?

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So the professor basically one day walks into the lab and he says, well, I have money for you for two more months.

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Yeah, so you have to figure out whether you go back to Mexico, you find a job, or figure out where you are going.

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I know you want to do a PhD, so that was February, and then all the applications were already done.

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Oh yeah, so I basically look, and the only school that was still open was UT Austin.

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Yeah.

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So the only school I apply for a PhD was UT Austin.

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I apply in March.

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I haven't even take the GRE, so I took the GRE and then I interview in July and by September I was in doing my PhD in UT Austin.

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Yeah, it's funny how that works out.

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You don't even have to stress about where you're going to go.

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No, I have no option, but I don't regret it.

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I end up with the best mentor somebody can ask OK, good, and what did you study in grad school?

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So I was working with E coli in Dallas.

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So I went and when I end up in Austin, I look for the only professor that was working with bacteria.

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And she was working with sister bacteria to E coli called Shigala that also calls diarrhea, yeah, and she was working with Bibrocholera, a causative agent of cholera.

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Right, and I came and I said well, I want to work with E coli.

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She looked at me and said I don't work with E coli, but there was at the time a new category of E coli that was producing outbreaks.

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That's the reason we're talking to this new E coli that was associated with consumption of undercooked beef.

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And then she got interested and she said OK, you are the only one that is going to work with E coli in my laboratory.

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So I did a PhD in this new E coli that was associated with consumption of undercooked beef.

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That's how I got my PhD.

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Yeah, I remember a situation back in probably the early 90s with a jack in the box and an undercooked hamburger.

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I think it was just like a singular accident, but somebody died.

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That was E coli.

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Is this this kind you studied in grad school?

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That's it.

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That's 1982.

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It was 82.

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1982 is when you name the fast food the fast food change I remember it.

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But yeah, it was interesting because this fast food change was located between the United States and Canada.

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So there were cases in Minnesota and in the other side in Canada and the two groups from the United States and Canada are investigating and they found out that this was new isolate that has never been reported before that was causing these infections and in the United States the people that investigated they call this bacteria she got toxic, producing E coli, so it produced a toxin.

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In the Canadian side they didn't like to use the American designation so they call it neurotoxin E coli because they isolated in bureau cells.

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So in Canada it's called toxinic E coli, In the United States called she got toxic E coli, but that's the same bacteria.

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OK, but it was a sourdough jack.

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Yes.

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Well, it sounds like a super, like awesome project for a grad student.

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A new bacteria that's causing disease that no one's ever reported before.

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So have you always been interested in bacteria that causes diarrheal disease?

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I think so.

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I guess that was my passion for many, many years.

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And to continue the story, I finished my PhD and then I looked for a lab that was also studying this bacteria.

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Right, so I did a postdoctoral training in Baltimore where I was studying this bacteria and trying to figure out how this bacteria was causing disease.

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Yeah, and then I moved on to become an assistant professor and we have continued working with this bacteria and I love now develop vaccines and we have effective vaccines against these bacteria.

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But they are still causing disease.

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Right, so we are.

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We haven't done the job, correct I have a question about that vaccine.

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So would the vaccine be for people who are working in the beef industry or who have a higher potential for exposure, or would it be something that would become a childhood vaccine, along with all of the ones we give our children when they're young?

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So the original vaccines that were developed.

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We have to tell it with more of a story.

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So turns out that this bacteria is found in the gastrointestinal tract of cows, and cattle do not develop disease, they like to have this bacteria in there.

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The bacteria leaves, happily, is particularly close to the rectum and the anum in the in the in the cows.

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And once we consume the cow and they open the cow, the carcass to to trade, to take the meter we're going to consume, it gets sometimes contaminated with intestinal tract bacteria and that's how you contaminate the meat that we're going to consume.

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So the original idea was to try to develop vaccines that were used in cattle and then reduce the load of bacteria, especially this E coli that we're talking about, and then when we consume the meat, then we'll not have this potential bacteria.

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The problem is that ranchers and people that raise cattle we're in Texas, so there is ranch that have 100,000 heads of cattle and the vaccine costs like two, three dollars each and you have to give two doses.

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The ranchers say, no way, I'm not going to spend money in a vaccine that does not cause disease in cattle, so it's not going to do anything.

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So there's two effective vaccines against cattle that are no use.

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So the idea now to develop vaccines against humans.

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Potentially there is areas that are endemic around the world still with this bacteria, so the idea is to potentially give it to those individuals that are not susceptible.

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Mainly the most susceptible kids to this bacteria are kids under age of five or elderly people.

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So the idea is to target it and then give it to them in those countries that they suffer the majority of these cases.

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And it's foodborne.

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I mean, if you're going to get E coli, you're going to get it from food.

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Yes, absolutely, absolutely.

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So let's back up a little bit and talk about E coli generally.

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You kind of mentioned that it's in cows, but it's not just in cows, right?

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We humans have E coli in our intestines, yeah.

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All mammals have E coli in their intestines.

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Yeah.

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That doesn't mean that all E coli that we carry are bad.

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It's part of our microbiota.

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Yeah, and we need it, we need bacteria.

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So there is very small group of these E coli that through evolution have acquired what is called virulence factors, so those genetic components that produce either toxins or adhesions or other factors that allows the bacteria to.

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You can imagine the bacteria wants to attach to something.

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In this case we'll attach to the intestinal and epithelial cells the lumen.

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They will attach because if they don't attach with the flow going through the intestine they will be washed away, right.

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So they want to attach and then they want to use nutrients, so they're attached to the cell.

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So how do you get nutrients from a cell?

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Well, you want to attack the cell, break the cell open and get the nutrients from the whole cell and then the bacteria will eat them.

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So how do you kill the cell?

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Well, you produce toxins or you produce other factors that are going to actually break open the whole cell and then the bacteria will eat them.

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The problem is, when those toxins are produced they are not just staying in that cell.

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They can go to the bloodstream, to particular organs, and then cause other problems.

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Right.

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So I have a question If the bacteria is killing the cell it's adhered to, does it then get released to find another cell to adhere to?

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Or is it kind of only adhering to maybe a neighboring cell and killing one of?

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the neighboring cells.

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Yeah, there's a theory that I use when I try to teach my students in particoninobacteriology is that sometimes many of these bacteria they don't really want to kill you.

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You are killed because it's an accident, Right Well, they really want to go outside because they like to live in the environment, and I assume this E coli likes to live in the intestine of cattle.

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They don't like to be in the intestine of humans.

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Maybe it's not the right environment for the bacteria.

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Right.

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So the bacteria is producing a toxin, getting the nutrients and trying to get out In the process.

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Unfortunately, they can kill you yeah.

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I think this is such an interesting idea, that some bacteria are good and some are bad and some are good in some places.

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E coli is fine in your intestines as long as it's not one of the burial strains, but it can cause UTIs and a lot of other infections if it moves to a different part of your body.

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And I think one thing that people don't realize is in the space that you occupy.

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There's more bacteria cells in the space you occupy than there is human cells, which is, I think, just so amazing.

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When we talk about the microbiota and the microbiome, it's something word that we just throw out that, oh yeah, we have a few bacteria living in us, but we're actually more bacteria than human 85% of our body mass is bacteria.

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Yeah, microorganisms.

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Because there's viruses and phages.

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Fages that live inside the bacteria.

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Exactly yeah.

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So I think for me that always is so amazing, I agree.

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And when you were talking a few minutes ago and you were saying, oh, e coli doesn't like living in humans, it's like it has a mind of its own.

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And when you start to think about bacteria as this living thing that, like you said, it doesn't mean to kill you, it actually wants to be there and just survive itself right.

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Absolutely.

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And again the other example, thinking about that there is some E coli in urine testing that likes to live in urine testing, those part of the microbiota.

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However, you might perhaps hear that when you are growing up especially females they might develop urinary tract infections and that's because a bacteria that was in the intestine of these individuals accidentally find their way to the urinary tract and they cause an infection.

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So in one place the bacteria is not causing an infection, but in the wrong part of the body they become pathogenic.

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So these individuals will have this infection and then you can treat it.

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But sometimes it's really difficult to treat because it's a bacteria that is adapted to your body and knows how to live in your body and that's how you get that.

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So urinary tract infections normally they don't come from elsewhere, normally they come from inside us.

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Yeah.

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So what kind of antibiotics would treat E coli?

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Is that how you would treat something like that?

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Yeah, antibiotics normally treat all types of E coli.

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The majority the one that we're talking about that is associated with B, is the only bacteria that cannot be treated by antibiotics and there is an explanation for that.

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So you want to hear it?

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Yeah, so the bacteria that is associated with B contamination and the one that we have been describing and now lately has been associated with letals and spinous contamination, because the bacteria now found their way to survive in other environments.

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This bacteria, as I was telling you a few minutes ago, is called Shiga toxin, producing E coli.

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So the unique feature of this bacteria is that it produces a toxin and the toxin can kill intestinal cells.

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But the bad part of the story is that the toxin can travel through the bloodstream and go to the kidney and then this toxin, as I told you before, find receptors, and the receptors for the toxin are found in the kidney cell.

00:18:41.974 --> 00:18:50.921
So the toxin goes to the kidney cleaves, these receptors, and there is a general malfunction of the kidney because it cannot process protein synthesis.

00:18:50.921 --> 00:18:55.960
And then the individuals having the toxin in the kidneys basically have kidney malfunction.

00:18:55.960 --> 00:19:04.821
They can die and from a complication called hemolytic urimic syndrome, which is basically kidney malfunction, and those surviving from the infection.

00:19:04.821 --> 00:19:08.940
Actually, they need dialysis for the rest of their lives or kidney transplant.

00:19:08.940 --> 00:19:23.673
So I'm telling you all that for the following reason you asked me about antibiotics this toxin, the genes encoding for this toxin, are found in a component in the genome of these bacteria, thisophage, and this phase is part of the genome of this E coli.

00:19:23.873 --> 00:19:29.614
If you give antibiotics to a bacteria, the bacteria starts sensing that the antibiotic is in the environment.

00:19:29.614 --> 00:19:33.892
So if you are a bacteria and there is an antibiotic, the bacteria doesn't want to die.

00:19:33.892 --> 00:19:38.422
The bacteria has to activate what is called SOS mechanisms to try to survive.

00:19:38.422 --> 00:19:43.762
And one of the SOS mechanisms that the bacteria activates is start producing more toxin.

00:19:43.762 --> 00:19:49.148
Instead of having one copies of the toxin, start getting hundreds of copies of the toxin.

00:19:49.148 --> 00:19:54.221
So if the bacteria dies because of the antibiotic, can you imagine how many toxins are released?

00:19:54.221 --> 00:20:17.009
So at the beginning, when they were investigating this 1982 outbreak, the way they connect the two things is that they found these people eating in this fast food chains with the development of hemolytic urimic syndrome, and years later they found out that the reason there were so many hemolytic urimic syndrome cases is because the physicians were treating with antibiotics.

00:20:17.009 --> 00:20:19.296
So if somebody is listening.

00:20:19.296 --> 00:20:28.602
If you want to learn one lesson from this if you get E coli for food contamination, it's the only bacteria that physicians should not treat with antibiotics.

00:20:28.750 --> 00:20:29.632
Yeah, for sure.

00:20:29.632 --> 00:20:37.714
So it's almost like when your body mounts an immune response and responds to a pathogen or a bacteria or anything.

00:20:37.714 --> 00:20:39.198
This is the flip side of that.

00:20:39.198 --> 00:20:46.540
This is the bacteria reacting to something you thought might be a cure and creating even more toxin.

00:20:47.021 --> 00:20:51.461
Wow, yeah, but again, it don't want to give the impression that antibiotics do not work.

00:20:51.650 --> 00:20:51.810
No.

00:20:51.830 --> 00:20:57.702
The antibiotics work perfectly against all E coli and even this one will die with antibiotics.

00:20:57.702 --> 00:21:01.800
But if the bacteria is carrying the Siga toxins, that's counterindicated.

00:21:02.069 --> 00:21:02.852
So I have a question.

00:21:02.852 --> 00:21:08.872
There's more than one strain of bacteria that produce Shingatoxin In this outbreak.

00:21:08.872 --> 00:21:13.643
I know it's a bacteria called O 103, because we're just giving bacteria numbers.

00:21:13.643 --> 00:21:17.421
Now how is that different from other Shingatoxin producing bacteria?

00:21:17.730 --> 00:21:27.904
Okay, so within the family of Siga, toxin producing E coli, we have a way in the laboratory to identify some of the features of these bacteria and then we can classify them.

00:21:27.904 --> 00:21:35.222
So we use Sira that has rays against components of these bacteria on the surface and they react to different components.

00:21:35.222 --> 00:21:50.602
So there is a component in the bacteria called lipopolysaccharide that is a common part of the structure of the bacteria and different E coli carries different antigens in that lipopolysaccharide that if you use a Sira specific for that O-antigen you can classify it.

00:21:50.810 --> 00:21:53.028
So they're basically a little bit of a different shape, right.

00:21:53.530 --> 00:21:54.192
Exactly, exactly.

00:21:54.192 --> 00:21:57.422
The sugars are in a different way so the antibody can recognize that.

00:21:57.422 --> 00:22:08.628
So we in the laboratory we assign numbers, so it's the O-antigen, and then we assign numbers so you can find that the O-157 was the original bacteria that was causing this disease.

00:22:08.628 --> 00:22:11.960
So it has the O-antigen called antigen 157.

00:22:11.960 --> 00:22:16.233
But there is other ones now that we have found that also carry the Siga toxin.

00:22:16.233 --> 00:22:19.710
So the Siga toxin is in a phase and can move to other E coli.

00:22:19.871 --> 00:22:20.573
And what's a phage?

00:22:20.573 --> 00:22:21.255
Just remind us.

00:22:21.476 --> 00:22:25.309
The phage is a virus-like particle that infects bacteria.

00:22:25.430 --> 00:22:25.671
Right.

00:22:25.671 --> 00:22:36.451
The interesting thing about phages is it's a way that genes can move from one bacteria to another, because the virus or virus-like particle is essentially bringing genes from one bacteria another.

00:22:36.451 --> 00:22:49.913
So it's not that the bacteria is inheriting it from its parent bacteria, it's moving horizontally to like its neighboring bacteria, which is super cool and interesting and kind of special for bacteria.

00:22:50.173 --> 00:22:51.876
I'm so proud you were my student.

00:22:51.876 --> 00:22:52.939
Very interesting.

00:22:52.939 --> 00:22:59.623
So, if you can imagine, obviously there's 100 different O-antigens.

00:22:59.623 --> 00:23:04.417
Not all 100 bacteria that has these antigens cause disease in humans.

00:23:04.417 --> 00:23:07.911
So there is some O's that actually associated with disease.

00:23:07.911 --> 00:23:13.064
So in those that carry Siga toxin there is what is called the big six.

00:23:13.064 --> 00:23:23.469
The big six O-antigens, so O-157, o-26, o-113, o-103, those are the ones that cause disease in humans.

00:23:23.469 --> 00:23:24.372
So there's the six.

00:23:24.372 --> 00:23:28.607
In the United States we have six of them and they are all found in cattle.

00:23:28.607 --> 00:23:30.653
They do not cause disease in cattle.

00:23:30.653 --> 00:23:33.642
I guess we can talk about the outbreak and how this happened.

00:23:33.970 --> 00:23:40.973
Yeah, so I guess in this particular outbreak the beef was recalled because they found evidence of O-103.

00:23:40.973 --> 00:23:46.930
And it's interesting because apparently most laboratories only test for O-157.

00:23:46.930 --> 00:23:47.992
Is that true, correct?

00:23:47.992 --> 00:23:48.734
Do you know why that is?

00:23:48.796 --> 00:23:55.778
Well, O-157, since the beginning, was the most common O-antigens that was identified.

00:23:55.778 --> 00:23:57.803
But what has been found?

00:23:57.803 --> 00:24:34.220
And again, let me back up a little bit to explain when the first outbreaks happened in 1982, USDA and CDC start paying more attention about what was going around and then they're realizing that there were more outbreaks and every year we have outbreaks in the United States that we don't hear because they are no major, because the USDA implemented these rules and the USDA indicated that when you have a lot, millions of pounds of beef, they sample and they look for these big six and when they identify one of them, the rule is that you have to basically eliminate everything.

00:24:34.220 --> 00:24:36.104
Everything is gone.

00:24:36.104 --> 00:24:38.048
So that's what happened in this case.

00:24:38.048 --> 00:24:44.680
So normally, many places that they are looking for this, normally they look for a 157 because it's the most common one.

00:24:44.680 --> 00:24:48.315
But the rule, the law, indicates that they have to look for these six.

00:24:49.096 --> 00:24:54.984
Yeah and gosh, they had to recall 1.7 tons of beef.

00:24:54.984 --> 00:25:05.324
Just for you nerds out there, it's 3436 pounds of beef, which is really incredible, and I want to stress that no one actually has gotten sick, so it's only possible contamination.

00:25:05.324 --> 00:25:07.311
But still, that's just so much so.

00:25:07.332 --> 00:25:15.840
This was found in a processing plant through testing, but it was recalled, so it was already distributed, so it was found after the fact.

00:25:16.142 --> 00:25:31.047
Yeah, so it was packed on February 16th and I think at that time they had just checked for the most common one and I think, through this random sampling that they do when they randomly sample and do a more thorough look is when they found the 0103.

00:25:31.047 --> 00:25:32.356
I think that's how it worked out.

00:25:32.518 --> 00:25:33.359
Yeah and again.

00:25:33.359 --> 00:25:36.471
The interesting part of this recall is two ways.

00:25:36.471 --> 00:25:46.528
One is thanks to these new regulations that we have in the United States and in many countries, we normally do not get sick for consuming beef in the United States anymore.

00:25:46.528 --> 00:25:49.436
Because they do this, they have these massive recalls.

00:25:49.436 --> 00:25:59.806
A lot of factories and packing implants have gone bankrupt Because when these recalls talk about millions of pounds being recalled, they cannot recover from this.

00:26:00.027 --> 00:26:01.757
And they know that this is going to happen.

00:26:01.757 --> 00:26:09.099
So what is happening lately is now the bacteria doesn't cause infection by the consumption of beef, because you don't hear it.

00:26:09.099 --> 00:26:18.567
But perhaps you remember several years ago that you walk into any of your grocery stores and there was no bags of a spinners of lettuce.

00:26:18.567 --> 00:26:20.119
They were completely removed.

00:26:20.119 --> 00:26:22.165
So that was in 2000,.

00:26:22.165 --> 00:26:28.086
I think they figure out now the bacteria can actually survive in the leaves of a spinners and lettuce.

00:26:28.086 --> 00:26:36.167
And then we in the United States we'd a lot of bag pre wash spinners and lettuce that potentially might be loaded with these bacteria.

00:26:36.454 --> 00:26:36.756
Right.

00:26:36.776 --> 00:26:39.201
So that's another way we can actually get infected.

00:26:39.502 --> 00:26:50.042
I remember I've heard you recommend another thing that your mother told you to do when you're growing up about how to wash your lettuce, about letting it soak in a little bit of bleach water just to be certain.

00:26:50.042 --> 00:26:54.058
I remember that story and I've been doing it ever since.

00:26:54.058 --> 00:26:58.277
So yeah, just because it says pre washed, you should rewash it.

00:26:58.376 --> 00:27:12.771
The reason, Danielle, here some of my stories when I'm teaching the class is that when these cases were coming along, when you look at the bags, you pay attention, you're listening, and you go to the refrigerator open and look for a bag, they say five time wash.

00:27:12.771 --> 00:27:15.459
So I don't know how they wash a leaf five times.

00:27:15.459 --> 00:27:22.387
They turn around and they wash it five times, so literally they just rinse it and if the bacteria is inside there's no way to get out.

00:27:22.387 --> 00:27:26.721
So what Danielle was telling you about is one thing that I learned from my mom.

00:27:26.721 --> 00:27:29.708
We never ate any salad that was coming from a bag.

00:27:29.708 --> 00:27:34.646
So she caught it, she get the leaves and she submerged it in a water containing iodine.

00:27:34.646 --> 00:27:37.042
And then they sell these bottles of iodine.

00:27:37.042 --> 00:27:45.736
You can put some drops and let it soak in there and then wash it again with the idea of potentially eliminate any other bacteria that might be attached there.

00:27:45.736 --> 00:27:48.002
And always, always learn that from my mom.

00:27:48.324 --> 00:27:50.210
Yeah, that's interesting.

00:27:50.210 --> 00:27:50.913
I'm terrible.

00:27:50.913 --> 00:27:57.351
I buy a bag and I open it up and I do have the salad spinner so I wash it really good.

00:27:57.351 --> 00:27:59.458
But yeah, I'm gonna have to think about this.

00:27:59.458 --> 00:28:02.327
So it's not bleach, it's iodine?

00:28:02.407 --> 00:28:03.612
No, I don't know, it's.

00:28:03.772 --> 00:28:12.805
I think I'm confusing your stories of your mother with my stories of my grandmother, that's why we, that's why we clarify, that's why we clarify my grandmother used to soak all of our dishes in bleach.

00:28:12.845 --> 00:28:13.527
In bleach yeah.

00:28:13.994 --> 00:28:17.643
That's how she did it, which I think iodine is probably healthier.

00:28:17.762 --> 00:28:18.525
Yes, of course.

00:28:19.788 --> 00:28:28.782
Okay, so we've got this interesting story about the contaminated beef and if you're listening, I think we've gone over a couple of ways for you to protect yourself.

00:28:28.782 --> 00:28:29.744
And what are they?

00:28:29.744 --> 00:28:35.811
Wash your salad and if you're concerned, you can also just cook your meat appropriately.

00:28:35.811 --> 00:28:46.516
You're at risk here if you're eating rare meat, which is delicious I know rare steaks, everyone wants to eat rare steaks but if you're ever concerned about the quality of your beef, you just cook it all the way through.

00:28:46.516 --> 00:28:50.606
So is there anything else you think you want to discuss about E coli in general?

00:28:50.914 --> 00:28:58.097
Yeah, again, as we knew, technologies developing, we are finding new things about how bacteria can cause disease.

00:28:58.097 --> 00:29:02.092
So there was this recent story in the news, just I think a week ago.

00:29:02.092 --> 00:29:09.513
They found out that the majority of UTIs that are being happening comes from the gastrointestinal tract.

00:29:09.673 --> 00:29:10.537
Yeah some humans.

00:29:10.557 --> 00:29:21.367
So now there is a link, a distinct link, and they can actually use in sequencing to identify what particular type of E coli can be prone to cause urinary tract infections.

00:29:21.367 --> 00:29:23.359
So we are learning more and more about this.

00:29:23.359 --> 00:29:33.636
One of the recommendations that I do with my class is do not eat rare meat anywhere you go, especially if you go to countries where they have high prevalence of this bacteria.

00:29:33.636 --> 00:29:47.298
South America has the largest number of a hemolytic umicases 400,000 individuals because in Argentina, chile mainly Argentina they undercook the meat and there's a lot of kids getting sick there.

00:29:47.298 --> 00:29:48.462
And the United States.

00:29:48.462 --> 00:29:56.996
The good thing is we do not move meat around, so some areas have outbreaks and then they are concentrated in California and Nebraska, for example.

00:29:56.996 --> 00:30:01.847
Texas they never import meat from anybody else, so we're pretty safe in Texas.

00:30:01.847 --> 00:30:04.501
That doesn't mean that one day we will get an outbreak.

00:30:04.742 --> 00:30:13.946
In the future, as we see more increasing temperatures globally due to climate change, we can expect to see more diarrheal disease, particularly because of more bacteria.

00:30:13.946 --> 00:30:15.050
Why do you think that is?

00:30:15.372 --> 00:30:28.056
Well, if you want to think it as as simple as the following so the bacteria likes to live in environments that have higher temperatures, so you want to grow bacteria, you put 37 degrees and sometimes they grow faster.

00:30:28.416 --> 00:30:30.019
Is that 37 degrees Celsius?

00:30:30.079 --> 00:30:36.218
Celsius 37 degrees Celsius Instead of 30 degrees Celsius then the bacteria grows faster.

00:30:36.218 --> 00:30:51.686
So as the climate changes, the environment is perfect for potential bacteria that was not growing that fast to actually start populating other areas and potentially we get exposed to these higher numbers of bacteria and then getting disease.

00:30:52.135 --> 00:31:05.433
Right, and especially, I think, when you're thinking about meat being processed and it being processed outside or something like that being processed in elevated temperatures, lots more instance for contamination and bacterial growth and stuff like that.

00:31:05.433 --> 00:31:10.125
And even not just E coli, but other kind of waterborne bacterial pathogens as well.

00:31:10.184 --> 00:31:15.403
Yeah, that's a risk that we are going to have to figure out and face as temperatures are going up.

00:31:15.663 --> 00:31:25.823
Yes, so does that mean that the study of E coli is a growing science and that this would be the kind of thing that you would encourage students that might be interested in careers in science?

00:31:25.823 --> 00:31:29.336
Is there going to be a lot of interesting research in this area?

00:31:29.684 --> 00:31:34.656
I think microbiology in general is an interesting area to pursue as a career.

00:31:34.656 --> 00:31:38.375
It could be bacteria, it could be parasites, it could be viruses.

00:31:38.375 --> 00:31:41.534
There's a lot of things to be done and discover.

00:31:41.534 --> 00:31:44.309
There's every day you find something new happening.

00:31:44.309 --> 00:31:49.499
Potentially all depends on the funding and where the funding is going to these stories.

00:31:49.499 --> 00:32:04.155
So somebody in a scientific field has always said that the best thing that can happen to you as a scientist is that there is an outbreak with your favorite pathogen, Because potentially there is going to be funding that is going to be supporting your research.

00:32:05.186 --> 00:32:06.409
So I've got one last question.

00:32:06.409 --> 00:32:12.960
I don't know if Connie has any more, but if any of our listeners are interested in getting into microbiology, do you have any advice for them?

00:32:13.345 --> 00:32:13.707
Yeah.

00:32:13.707 --> 00:32:16.474
So, being quicet, obviously you have to like science.

00:32:16.474 --> 00:32:25.773
Yeah, you're not getting into microbiology because you're going to be rich, so don't expect that, but you have to be passionate about what you do.

00:32:25.773 --> 00:32:43.842
And then if you are intrigued by mysteries, as we discussed, and you're intrigued about potentially connecting social sciences with politics, with fast food chains and the federal government, and just do good for human beings, then that's your field.

00:32:44.082 --> 00:32:44.701
Right, right.

00:32:44.701 --> 00:32:48.605
Well, I think this has been a really great discussion and I've learned many things.

00:32:48.605 --> 00:32:50.704
I've learned I've got to wash my lettuce better.

00:32:50.704 --> 00:33:00.765
I've learned that the kind of E coli that we had this outbreak in recently with this beef and this recall is something that cannot be treated with antibiotics.

00:33:00.765 --> 00:33:18.404
I've learned that if you're interested in being somewhat of a science detective, that microbiology is a good way to go, and that you had a very lucky experience in getting into this E coli study, just sort of by a random meeting with a visiting professor.

00:33:18.404 --> 00:33:30.924
Correct, and so people should take advantage, as they're going to school and going to lectures and you never know where your opportunity that's going to lead you on your career trajectory may come from.

00:33:30.924 --> 00:33:33.230
So this has been a great discussion.

00:33:33.571 --> 00:33:34.594
Thank you.

00:33:34.594 --> 00:33:35.896
Thank you for the Thank you so much.

00:33:35.896 --> 00:33:36.318
Thank you.

00:33:36.930 --> 00:33:38.805
Thanks for listening to the Infectious Science podcast.

00:33:38.805 --> 00:33:46.805
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00:33:47.826 --> 00:33:55.444
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