Giardia and Clostridium in Dogs

Giardia is a parasite found in the intestines of many animals, including cats and dogs. It is easily spread by carriers, which are animals that have giardia but do not show any signs of illness. The primary sign of giardia is diarrhea or a bloody stool that may contain mucous.


Clostridium is a gram-positive bacteria that also causes diarrhea. It is particularly hard to control because it produces endospores, which is a capsule that protects the bacteria from extremes in temperature, starvation, gamma and ultraviolet rays, and many chemical disinfectants.

  1. Significance

    • Left untreated, giardia can cause complications of untreated diarrhea. Loss of fluid volume and electrolytes can potentially be life-threatening, especially in young puppies or older dogs with compromised immune systems. While there is no definitive answer, some research claims that giardia crosses species and can infect people.

      Clostridium may cause stomach cramps, minor food poisoning and diarrhea. More serious infections can lead to gangrene and severe colon infection, which can be fatal. Fortunately, most cases are relatively mild.

    Diagnosis

    • Giardia is diagnosed by examining a fecal smear under a microscope. Two important tests used are the zinc sulfate concentration test, and the ELISA test. The ELISA test, or enzyme-linked immunosorbent assay, detects the giardia antigen in the stool. The ELISA is very sensitive and reportedly detects 30 percent more cases of giardia than the zinc sulfate test.

      Definitive identification of clostridium requires a send-out test to identify the enterotoxin in the sample. The current preferred test is a reverse passive latex agglutination assay. Simply seeing the spores on a microscope slide does not make a definitive diagnosis, as clostridium is a normally present flora in the body. A negative assay test is not absolute.

    Treatment

    • Flagyl has been used for many years to treat giardia, but is only about 60 to 70 percent effective. Flagyl has some potentially serious side effects including vomiting, anorexia and liver toxicity. It cannot be used in pregnant dogs. In a recent study, Panacur, which is used to treat roundworm, hookworm and whipworm, has been shown to be effective in treating giardia. It is the drug of choice for treating pregnant animals. Flagyl is one of the few antibiotics that will treat clostridium. Other treatments for clostridium include Vancomycin, Bacitracin and Fucidin.

    Prevention

    • In 1999 GiardiaVax, a vaccine to manage giardia, was introduced to the market. It is not a preventative vaccine, but may lead to future vaccine development. To prevent diarrhea-causing diseases, dog kennels, runs and pens should regularly be cleaned of all solid waste. Steam cleaning or use of an ammonium compound can kill the cysts that carry giardia.

      Thoroughly wash your hands with warm water and soap after cleaning up feces or handling a dog with diarrhea. Use rubber gloves when cleaning waste. Diluted household bleach may be used to clean solid surfaces such as tile. Avoid letting your dog drink out of streams and ponds, and avoid unnecessary use of antibiotics.

    Warning

    • Never attempt to diagnose or treat illness in your dog on your own. If you suspect giardia or clostridium in your dog, take him to your vet immediately. Any other pets should be isolated from the sick dog, and should not be allowed in the area where the dog relieves himself. If your dog stays in a kennel or doghouse, it should be thoroughly cleaned following your vet's recommendation. Give your dog the full course of treatment prescribed, even if he seems better or the diarrhea has stopped.