Does anyone know for sure at what temperature Giardia, Cryptosporidium, and other water-borne nasties kick the bucket? I've always brought my water to a rolling boil before either using it or letting it cool down to drink, but is that really necessary? I can see a scenario where a person might have to conserve fuel, and if bringing it to, say, 200 degrees farenheit would serve as well, then I can see some advantages to not going all the way to full boil.

On a slightly different vein, suppose you are in a survival scenario and your food is spoiling/has spoiled. For example, all your cans of Spam and Del Monte green beans have bulges in them. Would cooking this food ever make it safe enough to eat? Are there common bacteria that can survive at 400 degrees for 6 hours and return to exact their revenge on you? (Palatibility is a subject for another day.)

Please note, I am well aware of the dictum "better safe than sorry." I would never dream of not coming to a full boil or eating spoiled food unless there was simply no other alternative than death by thirst or starvation. I'm just wondering if anyone knows the facts.

Regards, Vince