Giardia is a parasite that can affect the small intestine in dogs and cats. The number of strains of the disease are unknown, and researchers disagree on the particular effects of different strains of giardia.

Giardia is not very common, and infection and disease from giardia are even less common. The parasite often does not cause any symptoms in dogs.

Giardia Spread and Occurrence

A dog typically acquires giardia when he eats something that has the organism on it. The giardia will then open, release and divide within the small intestine.

Giardia and People

While certain types of giardia can affect people, it is unknown whether giardia of dogs can affect people. Researchers have still been unable to determine whether certain strains of the parasite will only affect certain species. Therefore, people should be very careful when caring for a pet that may have giardia, as the disease may be able to be passed on to them.

Symptoms of Giardia

Most cases of giardia do not create any signs or symptoms. When giardia does create symptoms, it’s most often in puppies or dogs with weakened immune systems.

These symptoms generally include:

  • abnormal feces (stronger than normal smell, greasy appearance or even abnormal color)
  • acute (sudden and severe), chronic (lasting continually over a long period of time) or intermittent (sometimes present, sometimes not) diarrhea
  • weight loss.

Giardia symptoms occur because the parasite is causing damage to the lining of the intestine, preventing proper absorption of nutrients and preventing digestion from occurring in the way that it should.

Giardia Treatment Methods

Treatment for giardia is a bit controversial and quite complicated. Researchers disagree on whether or not it’s a good idea to treat giardia if it’s found in the system but is not causing symptoms. Because of the possibility of transferring giardia to people, sometimes the parasite is treated even if it is causing no harm to a dog.

The treatment methods themselves are also controversial, as they are not always effective and can have some serious side effects. One medication (metronidazole) may cause liver damage in animals but is usually effective, and another (quinacrine hydrochloride) is not very effective and is a safer option, but can have these side effects:

  • anorexia
  • fever
  • lethargy
  • vomiting.

Researchers are also not sure if these treatments remove the entirety of the parasite or if parts can remain in the intestine even after treatment.

Prevention of Giardia

Preventing your dog or puppy from getting giardia is not always the easiest task. As it can be present in the feces of other dogs, many places would need to be avoided, such as:

  • certain lawns
  • kennels
  • local parks.

Part of the problem is that the parasite can live for months outside the host, especially in cold and wet environments.

Dogs must also be kept away from possibly contaminated water sources. Don’t let your dog drink from lakes, swamps, streams, ponds or puddles.

Using disinfectants and cleaners frequently in your home and making sure your dog’s conditions are sanitary can also help to prevent him from getting giardia. Ask your veterinarian if giardia is prevalent in your area. He may have more tips on prevention.