With Particular Attention to the Sierra Nevada
By Robert L. Rockwell, PhD
Ask the average outdoors person about Giardia lamblia or giardiasis, and they have certainly heard about it. Almost always, however, they are considerably misinformed about both the organisms prevalence in wilderness water, and the seriousness of the disease if contracted.
With the advent of the Internet, the amount of information one can easily find on the subject is voluminous. Unfortunately, most of it is flawed in important aspects, being unsubstantiated, anecdotal, or merely quoting other unsubstantiated and anecdotal articles. Official sources, such as many informational publications put out by the US government, are not immune to this criticism.





