I have had this problem. I think most of us have at some time in our lives.
You wipe your butt and you come up with a little blood. Nothing serious. Maybe a tiny hemorhoid ----or you are generally sore down there or some damned reason or other not very serious.
So we got an open wound, bleeding some. And feces in the general area. Miraculously it all heals within a few days. No problemo at all.
So why don’t any of us die of some horrible infection? I have heard that feces smeared on a wound is a terrible thing to happen. --------guaranteed infection n’est-ce pas?
So possibly it is because it is my own feces that I am dealing with-----and therefore cannot infect me–because I am dealing with my own immune system----But I really don’t understand how all this works.
I am pretty sure if I wiped somebody elses feces on an open sore on my body and did not treat it in any way----I would get a very serious infection.
Suppose (not really going to try this) I wiped some of my own feces on an open cut somewhere on my body (a shaving cut for example) -----would it not get infected?
Mea Culpa, sorry. Of course I meant “couldn’t” and I really did contemplate it before posting, but it was just too tempting to pass up. I’ll try to restrain myself in future.
Warning: Some immunologic observations mixed with speculations (by myself and the medical community at large follow).
Feces wiped on open wounds in places other than the peri-rectal area will spell big trouble. Those places on your body are not supposed to have high concentrationsof coliform bacteria there. Nasty things can often result.
Feces by bleeding hemorrhoids, fissures, fistulae or other lesions in the rectal area can cause problems too, but they do so at a far lower rate than would be expected, based on the “open wound smeared with feces” studies done on other body sites. Bottom line (no pun intended) seems to be that natural selection has produced folks who don’t get septic and die every time they have rectal irritation.
Which makes sense when you think about it. If a body didn’t have some natural tolerance for its own bacterial flora, it’d never live to reproduce. Last I heard, immunologists are still working on the exact mechanism by which the body recognizes its own pathogens and antigens, but haven’t nailed it down yet.
However, if a person becomes immunosuppressed, such as with HIV, or suppresant drugs for transplant patients, or by therapy for cancer, then we do see the frequency of getting those types of peri-rectal infections skyrocket (in addition to seeing oral infections by standard mouth organisms climb too).
In short, the body works in mysterious ways, but usually recognizes its own.
Having recently begun to see blood on the toilet paper in startling quantities almost every time I poo, I have been wondering this myself lately. Thanks for bringing it up, ombre3. And even more thanks, Qadgop, for the summary of the state of our medical knowledge about this particular issue.
No kidding. I saw blood once and was calling a doctor before I finished drying my hands. Turned out to be a hemorrhoid, but it was my first one. Sigh - nothing like the first time…
Heh heh … yeah, I did. It’s just minor hemorrhoids. I just wondered why the germs that could kill me if I started chowing down on feces didn’t kill me when exposed directly to my bloodstream.
according to that always-useful book End Product: The Last Taboo (a book all about poop), laboratory tests show that bits of a person’s own feces applied to skin in the perianal area will indeed cause rashes, so the body apparently doesn’t always recognize its own. A good argument for thorough wiping. It still doesn’t answer the OP’s question, and, in fact, makes it even more mysterious.
Gross question, but important and interesting.
This brings up a side issue I’ve often wondered about, but I don’t want to hijack the main thread – is it just fortuitous that Man, the only animal that Needs to Wipe (since we habve those uniquely human large buttocks) is also the only animal with the Opposable Thumbs that allow him to? Or did other creatures with the same issue just die off because they didn’t have those opposable thumbs?
Our cats can (they do it all the time, company or no) and dogs can, but I’ll bet apes can’t. Nor cows, horses, and lotsa other beasts who don’t have human buttocks.
Is it the antibodies in the blood that provides the resistance to infection? It would seem to be something else since I’d figure we get the same blood routed everywhere, like something (insert handwaving medical terms) within the skin tissue or cells?
If you grafted rectal skin somewhere else, say for a face transplant or something :dubious: , would it still be fecal-infection resistant at its new grafted location?
Obviously, I have no medical training, but the OP is a curious question.
