Giardia: Single-celled parasite.
Common in: Dogs living in kennel type situations (shelters, pet stores, etc.)
Can be found in: Intestines of dogs, cats, and humans.
Diagnosis: Microscopic fecal exam from very fresh fecal specimen. Note: False negative tests are common, so treatment without verification is common.
Treatment: Oral medication.
Possible Symptoms: Intermittent or continuous diarrhea, weight loss, depression, and a loss of appetite.
Possible Transmission: Infected feces contaminating the yard.
Lifestyle Prevention: Careful disposal of all fecal material; cleaning contaminated areas.
Medical Prevention: Vaccination. Note: Effectiveness of the vaccination is questionable at this time.
Zoonotic Transmission: Yes; wash hands and utensils.