CDC report on a choNElera outbreak in Tanzania.
they are giving out NaDCC tablets to chlorinate the water.
available from prepper sites, amazon and now from AliBaba.
Yes, chlorine bleach can be used in an emergency too, as can boiling water for 10 minutes and straining out the dirt/particles LINK
NEJM article on the importance of clean water.
it's not just cholera, which kills 3 to five million people a year, but simple diarrhea that is a major cause of death in young children, not to mention typhoid fever...
we helped villagers dig wells when we worked in Africa, supplying the expertise and pumps while they did the work. Alas, they were shallow wells, and the local latrines were the woods, so they did not always result in clean water, but hey, it's easier to boil or treat water from a local pump than it is to do it after you carried a gallon on your head for a mile or two before arriving home.
Here in the Philippines, we used a ceramic water filter for drinking water, until Lolo dug a deep well. However, the local city water is now a lot cleaner and more reliable than in the past, so we mainly use our pump for emergencies, such as the typhoon a couple years ago when electricity and water was out for a week, and everyone was buying containers of water to drink or getting it from friends who like us had deep wells.
Indeed, with the last two typhoons, our electricity and water stayed on (and boy, they are finally digging sewers/ covered drainage ditches to drain the water off).
However, our water just reeks of chlorine, probably to insure it is clean in case of contamination, so we again have a large container jug of Lolo's deep well water that we use for our drinking water.