The chigoe flea (Tunga penetrans) is a parasitic arthropod found in tropical climates, especially South America and the West Indies. At 1 millimeter long, the chigoe flea is the smallest known flea. Breeding female chigoes burrow into exposed skin and lay eggs, causing intense irritation. After this point, the skin lesion looks like a 5 to 10 mm white spot with a central black dot, which are the flea's exposed hind legs, respiratory spiracles and reproductive organs.
If the flea is left within the skin, infection and/or other dangerous complications may ensue.
The free-living flea is a poor jumper and can only reach a height of around 20 centimeter; therefore the use of closed shoes (as opposed to sandals or slippers) is an effective way of preventing infection.
The parasitic flea lives in soil and sand, and feeds intermittently on warm-blooded hosts such as humans, cattle, sheep, dogs, mice, and other animals. In order to reproduce, the female flea burrows head-first into the hosts' skin, often leaving the caudal tip of its abdomen visible through an orifice in a skin lesion. This orifice allows the chigoe flea to breathe while feeding on blood vessels in the cutaneous and subcutaneous dermal layer. In the next two weeks, the flea releases about 100 eggs through the orifice, which fall to the ground. The flea then dies and is sloughed by the host's skin. Within the next three to four days, the eggs hatch and mature into adult fleas within three to four weeks.