I'm forwarding your post to bionet.parasitology. You may get
information there, also. I know what they look like under a microscope,
but don't know answers to your questions.
Judy Dilworth, M.T. (ASCP)
Ed Stevens wrote:
>> Hello, All.
>> I am an Assistant Scoutmaster with a Boy Scout troop in TN. I am
> heavily involved in training new adult leaders in basic outdoor
> skills. I am searching for some _authoritative_ information regarding
> the use of heat and iodine for purifying water in the backcountry. So
> far my research on the Web has led to a lot of stuff that was either
> over my head or dealt with treating public water supplies. I have two
> basic questions.
>> First, at what temp. are cryptosporidium and giradia killed, or at
> least rendered "not a problem." I have heard through unverifiable
> sources that the temp. is somewhere around 120 deg. F. If this is
> true, then I would think that even at the highest altitudes at which
> surface water is found the boiling point would be well above this and
> by the time water comes to a boil, regardless of the altitude, these
> nasties are dead. If this is true, then the common recommendations of
> "boiling for x minutes" are overkill.
>> Second, I have heard (again through unverifiable sources ) that crypto
> and girardia, being transmitted as a hard-shelled cyst, are not
> affected by common iodine treatment.
>> Comments on either of these? Are there any authoritative sources
> addressing these questions that I could use as a reference?
>> - Ed Stevens
> Ed Stevens/TN