|Description:||Under a magnification of 125x, this photomicrograph of an unstained mounted formalin-preserved fecal sample revealed the presence of a number of parasitic worm eggs, which included the eggs of a trematode, Fasciolopsis buski, an Ascaris sp. nematode, a Trichuris sp. nematode, and an unknown specie of nematodal hookworm, all for the purpose of a size comparison.|
A parasite is an organism that lives on or in a host and gets its food from or at the expense of its host. Parasites can cause disease in humans. Some parasitic diseases are easily treated and some are not. The burden of these diseases often rests on communities in the tropics and subtropics, but parasitic infections also affect people in developed countries.