[pct-l] Water borne diseases--more info about Giardia

[MAXINE WEYANT]

Thanks Yoshihiro,  
I've never even heard of some of those organisms. When I hiked the Carson Iceberg "Wilderness" section north of Sonora Pass one August, I kept frightening the cows and they'd run up the trail only to be frightened again when I rounded the next corner.  They left such a huge cloud of dust that I had to wear a bandana over my nose and mouth, and some left huge puddles of liquid poop that splattered up my legs when I stepped in them (couldn't see because of the dust.)  So much for pristine wilderness conditions.    Dys-feng shui-nal


> Date: Sat, 7 Jul 2012 09:29:28 +0900
> Subject: Re: [pct-l] Water borne diseases--more info about Giardia
> From: completewalker at gmail.com
> To: weyantm at msn.com
> CC: pct-l at backcountry.net
> 
> Dear Maxine
> 
> I have just consulted PubMed, on 'Sierra Nevada' and 'water', resulted
> 66 papers. Most recent paper may be the following:
> 
> J Environ Public Health. 2012. Impact of summer cattle grazing on the
> Sierra Nevada watershed: aquatic algae and bacteria. by Derlet RW, et
> al.
> 
> Abstract
> We evaluated periphytic algal and microbial communities to assess the
> influence of human and cattle impact on Sierra water quality.
> METHODS:
> 64 sites (lakes and streams from Lake Tahoe to Sequoia National Park,
> California) were sampled for suspended indicator bacteria and algae
> following standardized procedures. The potential for nonpoint
> pollution was divided into three categories: cattle-grazing areas (C),
> recreation use areas (R), or remote wildlife areas (W).
> RESULTS:
> Periphyton was found at 100% of C sites, 89% of R sites, but only 25%
> of W sites. Eleven species of periphytic algae were identified,
> including Zygnema, Ulothrix, Chlorella, Spirogyra, mixed Diatoms, and
> Cladophoria. Mean benthic algae coverage was 66% at C sites compared
> to 2% at W sites (P < 0.05). The prevalence of E. coli associated with
> periphyton was 100% at C sites, 25% of R sites, and 0% of W sites.
> Mean E. coli CFU/gm of algae detected was: C = 173,000, R = 700, W =
> 0. (P < 0.05). Analysis of neighboring water for E. coli bacteria >100
> CFU/100 mL: C = 91%, R = 8%, W = 0 (P < 0.05).
> CONCLUSION:
> Higher periphytic algal biomass and uniform presence of
> periphyton-attached E. coli corresponded to watersheds exposed to
> summer cattle grazing. These differences suggest cattle grazing
> compromises water quality.
> PMID: 22505950 [PubMed - in process] PMCID: PMC3312331 Free PMC Article
> 
> 
> This is a free article:
> http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3312331/pdf/JEPH2012-760108.pdf
> 
> Several abstracts were filed in my site:
> https://sites.google.com/site/completewalker/backpacking-memo/water
> 
> Cattle grazing has some impact to water quality. The remote wildlife
> areas (W) are relatively safe, but other areas are not safe.
> 
> 
> -- 
> Sincerely
> --------------- --------------------------------------
> Hiro    ( Yoshihiro Murakami  村上宣寛 )
> facebook  http://www.facebook.com/completewalker
> Blogs  http://completewalker.blogspot.jp/
> Photo  https://picasaweb.google.com/104620544810418955412/
> Backpacking since about 1980 in Japan
> JMT, 2009, 2010, 2011(half).
> ------------------------------------------------------