The main cause of Giardiasis is a single-celled organism called Giardia Lamblia.
The term “Giardiasis” is usually used to refer to the condition of being infected with the Giardia organism. Like most parasites, the organism is transmitted through ingestion of contaminated materials.
The Giardia parasite is commonly seen in dogs, cats, humans and birds. Other hosts may include mammals such as deer, beavers, sheep and cows. The parasite is able to infect a dog through ingestion of dormant cysts, which are commonly contained in the feces of infected animals. Other methods of ingestion include contaminated food, water or animal materials.
It is possible for a Giardia cyst to survive for several months, when provided with a warm water-based environment. Giardia organisms emerge from the cyst once ingested, and then proceed to enter their feeding stage. After this occurs, the Giardia Lamblia reproduces asexually, which produces more organisms. Some cysts and organisms are passed into the feces, though only the cysts are able to survive exposure outside of the host.
The primary mode of transmission for the Giardia Lamblia parasite is through ingestion of contaminated materials, as stated before.
Though it is not possible for the parasite to be transmitted through proximity contact with an infected animal or material, contact with infected fecal material, especially if ingested, is usually cause for infection. Many dogs are infected with Giardia by swimming in water that contains the parasite, since most dogs also drink the water at this time.
There is no specific type of dog that is more succeptible to Giardia. The Giardia Lamblia parasite is able to infect many different mammals, and is not particularly species-specific. However, dogs that are frequently exposed to areas where Giardia parasite is known to be present, do have a greater risk of being subjected to Giardiasis.