[at-l] what *IS* the risk of water borne pathology?

[Mara Factor]

In 1997, I picked up giardia while on the Long Trail in VT.  Whether
it came from the water there, a misused filter (I accepted water from
someone who I later realized didn't separate his input and output
hoses while storing the filter), or off the hands of someone with bad
toilet habits, I'll never know.

Either way, I didn't respond to the antibiotics my doctor prescribed
and since I was headed overseas, my doctors in Cambridge, MA gave me a
referal for a doctor in Kathmandu.  So, I traveled for a month in
China having one or two good days and then one or two bad days.  The
bad days were none too pleasant, especially when traveling in rural
areas.

Once in Nepal, Dr. Shlim at the CIWEC clinic fixed me up in three
days.  I had been living with symptoms for 2.5 months.  Just as I got
rid of the giardia, I got food poisoning for the first time in my
life.  I saw Dr. Shlim for that, as well.

Turns out this doctor, now working in Jackson Hole, is one of the
world's experts in both diarrheal and high altitude illnesses.  I
learned a lot both from talking with him as well as reading some of
the papers he had written and left in his waiting room for travelers
to peruse.  (These may be available online.)

For example, only about half the people who ingest enough giardia to
get sick will actually get sick.  Of those, half will be asymptomatic.
 So, that means, ~25% of those who ingest enough giardia to get sick
will not get symptoms but will be carriers and have the ability to
spread the disease without knowing it.

Also, apparently local populations often (always?) do not develop
immunity to pathogens but rather just get used to living with them and
perceive any "symptoms" they have as their "normal" not knowing
better.  Keep in mind, as poor populations, they often have no or
little contact with those from other parts of the world and therefore
nothing to compare themselves with.

So, even if you're one of the lucky ones who never seem to get sick,
keep in mind you may be contributing to others' misery.

Me?  I look at contaminated food or water and get sick.  Plus, I put
myself into situations where I'm more likely to get sick so end up
having to deal with the consequences.  When I travel to third world or
developing nations, it's easy to "boil it, cook it, peel it, or forget
it" if I'm traveling for a week or two, but when traveling for months
at a time, I prefer to eat what I want, when I want, and end up having
to treat myself for travelers diarrhea with some degree of frequency
(4-5 times this past year in Central and South America, for example).

When backpacking, I treat almost all of my water even though I'm
pretty sure almost all water sources are safe - at least along the AT.
 You just never know if something died just out of sight upstream - or
if the trail is about to switchback uphill, to pass the same water
source, etc.  I used to use iodine tablets and now use Aqua Mira.
Both are light and easy to use.

Mara
Stitches, AT99

Visit my Travels and Trails web site at: http://friends.backcountry.net/m_factor



On Thu, Nov 19, 2009 at 5:33 PM, David Addleton <dfaddleton at gmail.com> wrote:
> is there *really* a filter that guarantees to strain out virii??!! *all* virii?
>
> what's the *real* risk of the various waterborne pathogens from
> springs and streams on the AT?
> *real* means has there been any inventory of the extant pathogens
> published in the last 5 years? 10 years?
> any epidemiological study? any citations anyone can send my way?
>
> I hear a *lot* of advice to buy this or that filter, or use this or
> that treatment, but I've not seen any articles about the real risks
> involved and wonder if the advice isn't more marketing than reality?
>
> Eg., warnings notwithstanding, I drink from springs on Cumberland
> Island with no resulting pathology. On those occassions when I have
> selected springs along the AT from which to drink without water
> treatment, no pathology has resulted to me . . . . Similar experience
> choosing water in third world south and east asia: no resulting
> pathology drinking selected untreated water . . . .
>
> On Thu, Nov 19, 2009 at 4:28 PM, Tom Fort <tom at tjfort.net> wrote:
>> If you don't drink from a well, you are ingesting loads of chlorine every
>> day!
>>
>> t.
>>
>> Quoting JJJ :
>>
>> is it ok to be drinking bleach?  what's it do to the organisms in your gut?
>> probably don't want to kill them!
>>
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