Worldwide, a number of fatalities have occurred from a rare form of meningitis caused by an amoeba, Naegleria fowleri, that inhabits warm water and soil worldwide. The organism enters the brain through the nasal passages and produces a runny nose or sore throat, severe headache, and possibly death within a few days. Although no cases of this type have been reported to the National Monument staff recently, to avoid all possiblity of contracting this rare disease, bathers are advised not to immerse their heads, and to keep their noses out of the hot springs water.
Please be advised that giardia (scientific name: giardia lamblia) may also be in the local waters. If a person ingests even a minute quantity, infection can occur leading to nausea, cramps, bloating, and diarrhea. The resulting dehydration and weight loss can be serious enough to require hospital care. Hikers are advised to purify all untreated water obtained from rivers, streams, pools, etc. Giardia is more difficult to kill than most organisms with the usual water-treatment chemicals such as chlorine and iodine. Giardia cannot survive for long in water heated to 150 degrees Fahrenheit; boiling is not necessary, but does provide a safety factor. Proper filtration is another option to eliminate giardia; please check the filter manufacturer's specifications.