Giardia: Crypto’s Cousin

By: Michael Lamping, DVM

          This summer, cryptosporidium made waves in the news media due to several cases of human infection related to contaminated public pools and a lake in Dallas and Tarrant Counties.  This micro-organism raised concern when it led to instances of diarrhea in people.  While “crypto” can similarly affect cats and dogs, a close relative called giardia more frequently affects pets. 

If you’ve ever been warned not to drink the water straight from a mountain stream without boiling it first, then you may have heard of giardia.  Because this parasite can persist in the intestinal tracts of wildlife, it can be spread to people and pets when they drink water contaminated with fecal matter. 

At Murphy Road Animal Hospital, we occasionally see pets experiencing diarrhea due to giardia infections.  Found more often in puppies and kittens than in adult pets, this parasite is diagnosed from a test of the animal’s stool.  From January 1st through August 14, 2008, we have diagnosed giardia 19 times.  The significance of finding giardia infection should not be down-played.  Although most instances of human giardia cases are transmitted from person to person, the potential exists for spread from animals to humans. 

Giardia, a single-cell microbe called a protozoan, can lead to both sudden severe symptoms of intestinal upset and chronic symptoms of recurrent soft stools.  Among people, children and the immune-compromised are the most at-risk of acquiring giardia.  Appropriate handwashing technique and testing feces from puppies, kittens, and adult pets annually are helpful ways of preventing its spread.  Treatment is available through oral medications which must be administered according to specific instructions.  Following treatment, repeat testing is essential. Visit your veterinarian and www.petsandparasites.org for further guidance in preventing giardia and other parasites.