[at-l] Re: water filters...

[orangebug74@yahoo.com (Orange Bug)]

I'm not sure that this isn't already done. For instance, 2 years ago we
had the Norwalk Virus outbreak in Virginia related to a specific spigot
at a convenience store near the trail. The illnesses caught the
attention of local public health and CDC resulting in finding the
source of infection.

Giardia requires a fairly prolonged incubation period, when it is
clinically expressed. This would make epidemiologic study more
complicated, particularly as water is not the primary vector for human
to human transmission.

My point is that if water was a significant risk factor to hikers or
other members of the general public, we would see ER's and
port-a-john's flooded (sorry for the image) with soiled and foul
smelling hikers wasting away from dehydration and malnutrition. We
don't. When there is a local outbreak, public health has attacked the
problem with the help of victims, hikers and the public.

I think that the sort of study of sampling water would fail to find
significant problems in the absense of ill hikers. The would be false
positives that would unneccessarily alarm hikers and the public.
Valuable resources for public health issues would be diverted for a
unproductive wild beaver-fever chase. This would still fail to
demonstrate that filters or other water treatment has benefit, or that
hand washing is beneficial in the backcountry.

What would be interesting is the following study: 50 hikers are
recruited to collect water samples. All would be told they have special
sampling bottles that hold one ounce of water but is exquisitely
sensitive to contamination, keeping weight and resistance to the
procedure at a low level. 25 are trained to vigorously scrub and clean
hands with alcohol gel as part of the sampling procedure. The other 25
would be directed to simply dip and sample without direction for hand
cleaning. All water samples would be discarded on delivery to the lab.
All hikers would be contacted every three days, beginning 1 week before
their hike and 3 weeks following their hike regarding GI, headache and
itching complaints (the later as a placebo complaint). The study would
see if hikers who had frequent handwashing had any different GI
experiences. A medical student or public health student might find this
an interesting project to direct.

Bill...

--- Clark <icw39@ncfreedom.net> wrote:
> on the larger issue, i still think hikers such as myself could take
> good samples, and that the results would be valuable to the hiking
and
> scientific community - not so much for posting a specific water
> source as "bad," but rather as a tool for gathering general regional
> information re water quality...

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