Interactions
Giardia lamblia is a parasite belonging to the unicellular, multiflagellated, protozoa. In order for Giardia to survive it requires glucose as a energy source. It obtains this by feeding off the small intestine in an organism by either diffusion, molecules moving from high to low, or pinocytosis, where the cell engulfs broken down particles (Stanford). Not only does Giardia lamblia inhabit humans, but it has been found in up to 40 different types of animals including domestic animals like dogs and cats, farm animals like cattle, sheep, and pigs, and of course true to its name “beaver fever”, beavers (Krauss et all 2003). In these organisms, an infection of Giardia causes the disease called giardiasis. Giardiasis is a zoonosis, meaning it can be transferred from humans to animals and vice versa (Stanford). It is the most popular diagnosed intestinal parasitic disease in the U.S. and the most common cause of “travelers diarrhea” (Huang 2006). Giardiasis may be asymptomatic or include the symptoms of most commonly, diarrhea, gas, abdominal discomfort, nausea, and in extreme cases dehydration (Robertson et al 2010). The infection usually clears up on its own after around a week but may turn chronic, lasting from months to even years for the host (Berger & Marr 2006).
In one study done in Mexico City, out of 100 adult stray dogs tested in both the winter and summer seasons, Giardia was found in up to 40-50% of these dogs (Ponce-Macotela et al 2005). With over 120,000 stray dogs found in this city alone this poses a great concern of Giardia infection for surrounding humans and enforces the importance of fecal contamination prevention (BBC).