Re: [at-l] Hepatitis A on the AT

["W F Thorneloe, MD" <thornel@ibm.net>]

Actually, you are quite correct. The problem is in what the iodine is doing 
and what the filter is doing.

The 20 minutes of Iodine exposure is based on the idea of unfiltered water 
with Giardia cysts. Giardia is the toughest critter to kill, hence iodine 
needs prolonged exposure.

The purifiers work with first filtering (gets the larger cysts and 
critters) and then iodinating the viruses that pass through the filter. 
Viruses don't tolerate iodine, at all.

Hence, the belt and suspenders type of person would filter water and then 
iodinate it. The purifiers do this conveniently, but for a cost. It is all 
an individual decision. We won't even begin to discuss UV and other hi-tech 
controversies.

OrangeBug
Atlanta, GA

At 05:52 AM 10/5/1999 -0700, Amy Friends wrote:
>>Actually, Iodine should handle viruses quite handily. Purifiers (as 
>>opposed to filters) would do the same by adding iodine to the filtered water.
>
>Doesn't that presume the water is exposed to the iodine for something like 
>20 minutes?  I think the normal practice of pumping water through  a 
>purifier doesn't give enough exposure to kill viruses (virii?).
>
>Please correct me if I'm wrong, Doc - I just thought that I had read this 
>somewhere.

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