Giardiasis is a diarrheal illness caused by the parasite Giardia intestinalis (also known as Giardia lamblia or Giardia duodenalis). A parasite is an organism that feeds off of another to survive. Giardiasis is a global disease. It infects nearly 2% of adults and 6% to 8% of children in developed countries worldwide. Nearly 33% of people in developing countries have had giardiasis. In the United States, Giardia infection is the most common intestinal parasitic disease affecting humans.
""Giardia Lamblia" is a flagellated protozoan parasite that colonizes and reproduces in the small intestine, causing giardiasis. The parasite attaches to the epithelium by a ventral adhesive disc, and reproduces via binary fission. Giardiasis does not spread via the bloodstream, nor does it spread to other parts of the gastrointestinal tract, but remains confined to the lumen of the small intestine."
Human dirofilariasis caused by infection with Dirofilaria worms(a genus of roundworm). The symptoms associated with infection by these filarial parasites, which are transmitted to humans by zooanthropophilic mosquitoes, are characterized by mainly pulmonary and subcutaneous nodules.