SciDev.net reports that prickly pear cactus (Opuntia spp) can be used in a simple process to remove 98% of bacteria from dirty water. ((I worry about the other 2%, really I do.)) That would be good news for poor people who may be surrounded by prickly pears, but lack clean water. Alas, (some) poor people don’t want pure water.
“Stomach and intestinal infections are considered a way of cleansing the body, and are not conceived as diseases.”
Oh the dilemma. Preserve their indigenous knowledge, or offer them better health? ((Yeah, yeah, another damned binary choice, I know.))
Strangely, among other communities, on another continent, indigenous knowledge of the water purifying properties of Moringa seeds is just plain confused. Some people know all about it, others believe that more than three Moringa trees are “a source of misfortune that brings poverty and death”. But not from water-borne diseases, perhaps.
You can lead an indigenous person to water…?
The remaining 2% of bacteria sounds like the right amount to maintain the cleansing effect. Not everything is a binary choice.