racole <racole at FACSTAFF.WISC.EDU> wrote:
>I agree with Dr. Lindsay. I am not aware of references on surveys of
>back country waters and prevalence of Crypto or Giardia. We have always
>scared people with the threat of getting "beaver fever" etc, however,
>the literature that I am familiar with does not support this apparent
>overblown concern. All that I am familiar with are case reports where
>someone has been backpacking and later developed clinical signs of
>infection with Crypto or Giardia folllowed by finding oocysts or cysts
>in the feces. How many refs do you have of sampling free ranging
>wildlife or remote waterways?
Let's see - Jerry Ongerth has published quite a few papers about the
presence of Giardia and Cryptosporidium in source waters i.e., "Effects
of time and watershed characteristics on the concentration of Cryptosporidium
oocysts in river water" Appl. Environ. Micro. 57:2790-2795
Ongerth. "Giardia Cyst Concentrations in River Water" J AWWA.
The Journal for the American Water Works Association published pretty much
an entire issue on Cryptosporidium (September 1997).
There is also M. Chevallier and W. Norton, 1995. "Giardia and Cryptosporidium
spp. in raw and finished water" J. AWWA 87(9):54-68
Fayer, et al. "Survival of Cryptosporidium parvum oocysts in Seawater and
Eastern Oysters (Crassostrea virginica) in the Chesapeake Bay" 1998.
Appl. Environ. Micro. 64(3):1070-1074
Joan Rose wrote a very nice review paper about Cryptosporidium in the
journal Environmental Health (pg 80-87, don't have the issue info. - the
title is "Occurence and Significance of Cryptosporidium in Water")
Joan Shields jshields at uci.eduhttp://www.ags.uci.edu/~jshields
University of California - Irvine School of Social Ecology
Department of Environmental Analysis and Design
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