Definition

Parasites are organisms that live inside humans or other organisms who act as hosts. They are dependent on their hosts because they are unable to produce food or energy for themselves. Parasites are harmful to humans because they consume needed food, eat away body tissues and cells, and eliminate toxic waste, which makes people sick.

Because of sanitary living conditions in America, parasites do not cause widespread life-threatening infections. In other parts of the world, however, parasitic infections are epidemic. They kill and disable millions of people every year. Parasitic infection cases in the United States are on the rise due to increased travel to and from underdeveloped countries. In addition, parasitic infections can cause severe infections in