Kent Sepkowitz, a physician in New York City who writes about medicine, writes in Slate.com that,
"… one year ago, the now-famous E. coli outbreak arising from contaminated spinach rattled the natural-food industry and gave carnivores a moment of schadenfreude. The story had the heartbreaking elements we have come to dread: A young child eats something mundane and dies a horrid death. Boom, gone. I have (unsuccessfully) treated one such case and rate it as perhaps the most chilling moment of my career.
"With every outbreak, the same question sounds: Why can’t we keep the food chain clean? … The best response to E. coli and the other pathogens that cause food poisoning is to recognize, humbly, that we can get the food supply almost perfectly clean, but never completely. There’s just too much crap out there: human crap, horse crap, cow crap, pig crap. In the feces of these and other animals are trillions of infectious agents (bacteria, viruses, fungi, worms, and everything else that upsets the stomach). Try as we may to contain the mess, we can never win. Pig dung fouls rivers; cow crap seeps into water tables; human shit kicks back every time heavy rains overwhelm a sewage system’s filtration capacity. …
"Rather than frantically throwing money at new ways to eradicate the pathogens that reside in shit, we should fund the boring scientists who focus on untangling the intricacies of the gut’s immune system. Labs, answer this: How much shit can we safely eat and, as importantly, how much must we eat to remain healthy?"
While there is some truth in the doctor’s comments, humans just aren’t smart enough to figure out who is genetically susceptible to the various nasties out there. Maybe the population’s immunity can be increased by exposure to some cryptosporidium or salmonella or whatever, but individuals are gonna die. We’re gonna lose a few. And we don’t know who those few are.
So while we’re figuring that out, we have a responsibility to use the science we know to reduce the number of people who get sick from the food and water they consume. And don’t eat poop.