WHOA, A WHIPWORM Trichuris trichiura , commonly known as a whipworm because it looks like a cow whip, grows up to about two inches (50 millimeters, or as long as a thumb). The most common way to catch whipworm is by ingesting dirt containing human feces that are loaded with its eggs (think: children playing in the dirt and then putting their fingers in their mouths)... Courtesy of Parasitic Diseases, 5th Ed., Apple Trees Productions, LLC