Beaver Fever

Beaver Fever in humans is a diarrhea infection of the small intestine by a single-celled organism Giardia lamblia.
Giardiasis....
Unfiltered stream or lakes that may be contaminated by animal wastes are one common source of the inflection.  We really try to stay away from drinking ponds where Beaver lodges are present.  We look from small high mountain streams or seepages off hill side.
Prevention........ Boil the water for a least 3 minutes.
Once inside the body,  the parasite cling to the lining of the small intestine, reproduce and are swept into the fecal system.  As the liquid content of the bowel dries up, the parasites form cysts, which are them passed in the feces.  Once excreted, the cysts can survive in water for more than 3 months.
2/3 of infected people exhibit no symptoms.  Symptoms occur a week or more after infection.  When present, symptoms include explosive, watery diarrhea that can last for a week or more and in chronic cases, may persist for months.  High temperature and Fever is also present.
This parasite is all over the world.