4 ms·

I've read/heard some discussion about how humans suffer detriment now that we no longer have gut parasites living with us. Unfortuntely it's been rather thin on

I've read/heard some discussion about how humans suffer detriment now that we no longer have gut parasites living with us. Unfortuntely it's been rather thin on the ground, I suppose it's not a very glamourous area to study.

w1ntermute 11y ago
See An Epidemic of Absence: A New Way of Understanding Allergies and Autoimmune Diseases: http://www.amazon.com/dp/B0061P2L5U http://www.amazon.com/dp/B0061P2L5U
breischl 11y ago
I was thinking of the exact same thing. But I'm not sure it really applies, at least in the specific case of polio. Historically most people didn't have it, so we can't really be "missing" it. If we were talking about eradicating something relatively common and non-lethal, such as the common cold, that would be more comparable to the gut parasites.
- lolc 11y ago
  For polio, the hypothesis is that it was very common before 1900. I quote from "From Emergence to Eradication: The Epidemiology of Poliomyelitis Deconstructed" http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2991634/ http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2991634/ > In the pre-epidemic era, enteric infections were so ubiquitous that most infants were infected within 6–12 months, at a time when they had circulating antibodies passively derived from their nursing mothers. Although serum antibodies did not prevent enteric infection, they were sufficient to preclude viremia, thereby avoiding invasion of the central nervous system and paralysis. The result was the acquisition of active immunity under the cover of passive protection. So the hypothesis is that historically most people did have it and were immune, and only the improved hygiene past 1900 led to epidemics. We can indeed ask whether some individuals are worse off now because they didn't contract it in their infancy. But we're also doing pretty much the same thing with the vaccinations. Maybe we'll see a rise in allergic reactions when polio 2 vaccines are phased out. I don't think that anybody would advise infecting babies to get the benefits back though :-)
  - breischl 11y ago
    I stand corrected. Very interesting, thanks!
Amorymeltzer 11y ago
It's complicated, but the science is fairly well established that lack of parasitism has lead to increased incidence of allergies in developed nations. Small price to pay.
- egd 11y ago
  Autoimmune disorders are a large category - there's also some evidence that autism-spectrum disorders are caused by autoimmune responses in the mother.
- techdragon 11y ago
  Also keep in mind parasites and gut bacteria are far different to infectious diseases like polio and measles. We are rapidly approaching an era of medical treatments where giving a treatment of "probiotics" to correct your newborn child's gut bacteria in order to prevent asthma much the way we give immunisations against diseases today. The hygiene hypothesis is getting some pretty compelling evidence and hopefully it will lead to us learning the "right" kind of things we should be exposing our children to in order to prevent these autoimmune conditions.

w1ntermute 11y ago

See An Epidemic of Absence: A New Way of Understanding Allergies and Autoimmune Diseases: http://www.amazon.com/dp/B0061P2L5U http://www.amazon.com/dp/B0061P2L5U

breischl 11y ago

I was thinking of the exact same thing. But I'm not sure it really applies, at least in the specific case of polio. Historically most people didn't have it, so we can't really be "missing" it. If we were talking about eradicating something relatively common and non-lethal, such as the common cold, that would be more comparable to the gut parasites.

lolc 11y ago
For polio, the hypothesis is that it was very common before 1900. I quote from "From Emergence to Eradication: The Epidemiology of Poliomyelitis Deconstructed" http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2991634/ http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2991634/ > In the pre-epidemic era, enteric infections were so ubiquitous that most infants were infected within 6–12 months, at a time when they had circulating antibodies passively derived from their nursing mothers. Although serum antibodies did not prevent enteric infection, they were sufficient to preclude viremia, thereby avoiding invasion of the central nervous system and paralysis. The result was the acquisition of active immunity under the cover of passive protection. So the hypothesis is that historically most people did have it and were immune, and only the improved hygiene past 1900 led to epidemics. We can indeed ask whether some individuals are worse off now because they didn't contract it in their infancy. But we're also doing pretty much the same thing with the vaccinations. Maybe we'll see a rise in allergic reactions when polio 2 vaccines are phased out. I don't think that anybody would advise infecting babies to get the benefits back though :-)
- breischl 11y ago
  I stand corrected. Very interesting, thanks!

Amorymeltzer 11y ago

It's complicated, but the science is fairly well established that lack of parasitism has lead to increased incidence of allergies in developed nations. Small price to pay.

egd 11y ago
Autoimmune disorders are a large category - there's also some evidence that autism-spectrum disorders are caused by autoimmune responses in the mother.
techdragon 11y ago
Also keep in mind parasites and gut bacteria are far different to infectious diseases like polio and measles. We are rapidly approaching an era of medical treatments where giving a treatment of "probiotics" to correct your newborn child's gut bacteria in order to prevent asthma much the way we give immunisations against diseases today. The hygiene hypothesis is getting some pretty compelling evidence and hopefully it will lead to us learning the "right" kind of things we should be exposing our children to in order to prevent these autoimmune conditions.