Bug busters for water

Hikers and backpackers intent on minimizing the threat of giardia from backcountry water can try one of these methods that claim to banish the bacterial cysts.
Iodine
In the beginning, iodine was the chemical of choice for disinfecting water. Potable Aqua tablets purify a quart of water in 30 minutes - and come with a second tablet treatment that strips out the nasty aftertaste. Iodine is off limits to pregnant women and anyone allergic to it, but harmless when taken in the proper dosage.