Illness: This intestinal infection is caused by the protozoan parasite giardia, which is the most common intestinal parasite found in humans.
Symptoms: Diarrhea that is soft, frothy, greasy and emits a strong, awful odor; vomiting; weight loss
Who's Affected & Why: Nearly 50 percent of young puppies and up to 100 percent of dogs housed in kennels will develop this infection. Giardia is most commonly caused by the ingestion of infected fecal material.
How to Prevent & Cope: Be sure that your dog has clean drinking water. Often, it can be soiled with feces or dirt. In addition, pick up your dog's feces immediately and wipe them after they go. (petMD)