If you're worried about it, just carry along a small bottle of iodine or chlorine bleach, pre-diluted appropriately so that one drop would be sufficient to purify 4oz or water without being so strong as to cause YOU harm. You just want to nuke the bugs! Might not taste so good, but I survived many backpacking trips in the 70's drinking iodine water. Just don't boil starchy noodles in it unless you're willing to eat purple.