Just spoke with the microbiologist (PhD) at our lab and he has never
heard of giardia in the bloodstream.  It is a parasite which dwells in
the GI tract and cannot be compared to something like Toxoplasmosis which
does infect the blood and various internal tissues.  He does not see how
giardia could be transmitted into the breasts.

Also, I believe that some research showed that breastmilk is very
effective at killing giardia. Can't find the reference right now.

Sharon Knorr
Lactation Consultant Services
Rochester, New York
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