In the recent thread about the missing hiker with gastro/intestinal problems, one of the suggested, possible causes was a self infection due to poor hygiene after a toilet run. It sounds counter-intuitive that you can get sick from your own pathogens from/into the same pipe system but there must be a reason, does anybody know?

I understand that the pyloric valve in your stomach makes sure the passage of material to your digestive track is one-way, i.e. from stomach to duodenum, and doesn't allow nasties that live further along to get in.

Thus you do not want the stuff living in the parts past your (or someone else's) stomach to get into your stomach, and self-contamination can make you just as sick as cross-contamination.

Anecdotal evidence on the AT is that most digestive problems come from contamination, not bad water.

You have (and need) a lot of bacteria in your lower GI tract. You don't want them above your small intenstine (e.g. throat, stomach). A few people have infections that will make you very, very sick (typhoid Mary, Hep A, cholera), but everyone, including you, have normal gut bacteria that will knock you down for a few days if you ingest them. At home, you take a day off work, sit on the toilet a lot, drink fluids and take an OTC anti-dirrehal drug. On the trail the dehydration, loss of energy and mobility can cascade into a bad situation.

I have had serious gastro-intestinal surgery in the past, so I have to be extra vigilant about this. I've found that hand-sanitizer alone won't always prevent infections, so it's important to thoroughly wash hands with (eco-friendly) soap when possible. This is not to say that cross-contamination won't happen. So, I also bring an antibiotic with me—Xifaxin—which targets nasty bugs should they (in my instance, quite easily) make their way into my gut. Xifaxin targets just the "bad" bacteria, and leaves the rest alone. Nonetheless, augmenting my liquid intake with Ceralyte is essential in these instances. Xifaxin is a prescription drug, and its use/potential use should be discussed with your doctor beforehand—I'm just saying that a) I'm prone to infections despite my best efforts, b) I've found that it stops infections in their tracks when used.

Tim

Hand-to-mouth contanimation with e-coli bacteria is probably THE most common illness which backpackers suffer according to what my wilderness & Outdoor medicine manuals say.

I ALWAYS carry hand sanitizer in a Ziploc with my TP and use it liberally after a BM.

+1 with Eric.

Sanitizer lives with TP - that way there is no excuse, no forgetting.