Giardia

Is it true that once a dog has been treated for Giardia, that they are carriers.  And during times of stress or GI upset, it causes diarrhea?  I thought once treated, the parasites are gone from the dog's system.  

[Aleda M Cheng, D.V.M., C.V.A]

You should be able to rid your dog of giardia completely with one or more courses of anti-giardia antibiotics followed by the Giardia Vax vaccine, and than with annual Giardia Vax vaccine.  It may take several courses of antibiotic to completely eliminate the organism from the body, though.  Dogs who shed giardia are not "carriers" they are merely still infected.

The length of time for treatment is usually not long enough for persistant giardia infections.  Metronidazole should be given for 10 days to 14 days than the stool should be retested.  If the stool still contains giardia than continue treatment.  Panacur is also effective if given for 2 weeks.  The giardia protozoa is highly ubiquitous in the environment so re-infection is very common.  And of course,  it is transmissible to any species.