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Anna Crist

student researcher , University of Oregon

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Purell now, Bacteri-ell later?

The hygiene hypothesis, the idea that “too much cleanliness prevents the development of a well-balanced immune response”(Sironi and Clerici, 2010), has received a lot of support and also criticism. It has recently been challenged by the hypothesis of “early immune challenge”, which states that a lack of appropriate immune stimulation during early childhood might account for the increased development of allergies in industrialized countries (Kramer et al, 2013). This proposal places less emphasis on excessive hygienic practices and focuses more on the insufficient exposure to specific environmental microbes, particularly those from non-urban environments, as the reason behind the rise of atopic disease. While different, both hypotheses point to the beneficial health affects of some microbes.

What do you think is the reason for increased allergy levels in industrialized countries? Do you think that a concoction of the “right” microbial species in the form of a lotion, drink, or inhalant (aka "Bacteri-ell") could be a future replacement for natural exposure to beneficial microbes?
Instead of using hand sanitizers like Purell, do you see a future where people from some regions of the world are unsanitizing their hands with “Bacteri-ell”?


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  • Apr 30 2013: First of all, I know nothing about this cleanliness and health connection. My personal opinion is that allergies come about by what we eat, not by what we touch.

    We moved from the Netherlands to Canada close to 40 years ago. When we came here I was very much surprised by the severity of allergies. One of our kids went into a hospital for a small operation and my wife was reprimanded for not having filled-out his allergy list at the foot of his bed. When she said he did not have any, the were very surprised.

    I think all food there was organic and I hope it still is.
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      Apr 30 2013: Same here! I was surprised that many people have allergies or asthma when I moved to Hawaii. Until moving to Hawaii, I rarely see people who have allergies or asthma. I think that developing allergies and asthma is more associated with the environment, chemicals and pollutant. I mean microbes might be associated but more related to the environment?
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      Apr 30 2013: Yes, and not only to the present-day environmental conditions but years and years of human evolutionary history as well. There are distinct regional patterns in food allergies that can be explained by when those areas where first inhabited by humans many thousands of years ago. Since then, genetic mutations and genetic drift have changed the genome of certain individuals and those changes subsequently get reflected in the general population. A phenomenon in anthropology called "isolation by distance" basically means that there is little to no gene flow between certain populations because they are too geographically isolated from one another. The reason why we see allergies in some places and not others has to do with a genetic mutation that was maintained in one population but not introduced into another population because there was no interbreeding.
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        Apr 30 2013: Good point! I like that!
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      Apr 30 2013: I noticed a similar change in myself when I moved from Illinois to Oregon, a much less drastic change in environment than your move from the Netherlands to Canada. I never personally experienced allergies in the midwest but in Oregon I have them worse than ever. While it is possible that your child's allergy experience was due to food, I believe that this phenomenon is more likely to occur from the difference in the microorganisms present in the two environments. Being that most ecosystems differ from each other in their microbial makeup, is it possible that, upon moving, we are exposed to organisms that we have never encountered, causing reactions in our bodies (like allergies)?
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        Apr 30 2013: Yes, definitely! Diet matters! Food is one of good sources to get microbes, and where it is grown! Different habitat carries different biodiversity!
      • Apr 30 2013: Seems this was so much the case ages ago when Europeans went to South and North America and Mexico, which killed so many natives with them just being there.

        Now we have to get shots when going to many other parts of the world.

        Carty "While it is possible that your child's allergy experience was due to food,.."
        The point was he never, and still does not have any allergies.
        Does it not say, You are what you eat? :)
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        Apr 30 2013: I think environment absolutely plays a role, but not necessarily because of the microbial make up. Here in Eugene there is very heavy pollen in the spring and summer, so much so that I have heard many people say they didn't have allergies until they came here. We are indeed exposed to different organisms in different environments, and this is what can trigger an allergic reaction. Exposure is the key: you don't know you're allergic to something until you encounter it. Is it that more people are naturally becoming allergic to peanuts, or is it that--due to market integration and transportation--more people are eating peanuts now and discovering their allergies?

        I also think there is a lot of over-reporting/over-diagnosing with allergies. If someone has a negative experience with something it is easy to label it as an allergy. It is hard to tell the difference between hayfever and a common cold. If you get a cold in the springtime, and people ask if you have allergies, I believe most people would assume they did without second thought. The same is seen in the skyrocketing of ADHD diagnosis is children recently. Is it really that more than 50% of all children in the US are born with ADHD? Maybe their behavior is due to the fact they are confined in classrooms for longer hours everyday in school. When you really think about it, how can you expect a 7 year old not to be fidgety sitting at a desk all day; doesn't mean they have ADHD. Correlation vs. causation!
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          Eun Min

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          Apr 30 2013: Oh, yes! As you said, you don't know if you have an allergy until you expose to it!
          In terms of high increase ADHD in children, I agree with you that it might be environmental matter! Another thing I noticed was how we assess children. I used to volunteer preschools and a traveling preschool which run by Maui county called "tutu and me traveling school." When people assess the children, they show cards with objects printed on. Then, children need to answer what the objects are. I thought it was ridiculous that one of card is a coat. Of course, children do not know what a coat is due to not seen it before. The weather in HI is hot, so we don't wear a coat, but a jacket.
          Children get marked off because they do not know what a coat is!
          When people assess children, they need to consider more about the environment where the children grow up with!
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      Apr 30 2013: Yes, as another anecdotal aside, as a kid, whenever I found an object, anywhere, the first step I took was to put it in my mouth. I was always getting in trouble for this. It was a problem. My sister was more obedient or less orally-fixated or something, so she did not do this.

      Growing up, even though my sister ate healthier than me and participated in more sports, she got sick MUCH more often than I did- not a crazy amount, but maybe a few times a year. I pretty much never got sick, and still don't. I can't recall the last time I was sick, and I had always wondered if these things were related, if I had strengthened my immune system with unsanitary habits as a child. Obviously this could be due to many other things, but it certainly could have played a large part; my sister and I are genetically similar (obviously) and were exposed to much of the same environments.

      CONFOUNDINGLY, however, I have had bad pollen allergies my entire life, especially grasses, while she has never had any notable allergies. This part makes me question aspects of the early immune challenge as well as the hygiene hypotheses, as I was certainly exposed to grass pollen as a child. I'm still waiting to be struck with my multi-annual hay fever up here in the grass seed capital of the world. . . . maybe all that local honey has done me some good.

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