Backpackers are not able to carry enough water for the short trips let alone extended tours. When you backpack you need to drink water and on hot days this could equal a gallon or more. You are faced with a choice. Drink from the creeks and suffer the consequences or use a backpacker water purifier.
All of those cute little animals out there including squirrels, mice, rabbits, voles, beaver, muskrat as well as nearly every animal in the wild harbor tiny cysts. These cysts are everywhere. Even birds harbor them. The cysts also live in the soil and are washed into the lakes and rivers during heavy rains. They get into the soil by way of the droppings of animals.
Beaver fever is an infection of the small intestine and once you get it you will certainly know it.
Those infected may experience an abrupt onset of abdominal cramps, explosive, watery diarrhea, vomiting, foul flatus, and fever which may last for 3-4 days before proceeding into a more sub-acute phase
It generally will last in your system for from three to six weeks and will result in a loss of weight and leave you weak and worn out.
So be fore-warned. Filter your drinking water. Do not even think of drinking from that little creek where the water is co clear. It is simply not worth it.
Once the parasite enters your body it can take from a few day to a week or more for it to incubate. Your doctor may prescribe a medication.
Purchase a good quality water filter to take along on your trip. The good ones have filters that will filter out even the tiniest parasites. The water passes through a charcoal filter first and then a micro filter. This is one item you should purchase carefully. There are a great variety of filters and you should read reviews by backpackers who have used them before you buy.
The units may weigh a little over one pound and some weigh over two pounds. It is a pretty small price to pay to carry that in your backpack.
The fever affects from two to five per cent of the population in developed countries and more than twenty percent or more in third world countries.