chigoe (chĭgˈō) [key] or jigger, small parasitic flea ( Tunga penetrans ) of the tropics and subtropics, including the S United States. Humans and their domestic animals are the main hosts. The fertilized female bores into the flesh (usually of the feet or legs) and feeds on the blood causing a painful, pustulous sore. She retains her eggs in her abdomen, which swells to the size of a pea. The eggs are expelled outside the host and hatch in the soil, undergoing complete metamorphosis. Significant infestations can lead to severe inflammation, ulceration, and fibrosis and in more extreme cases gangrene, sepsis, and even death. The chigoe is sometimes confused with the chigger. The chigoe is classified in the phylum Arthropoda, class Insecta, order Siphonaptera.