Tungiasis is a cutaneous parasitic infestation, typically limited to the feet, that occurs after a flea burrows into the skin. Most commonly, the female sand flea Tunga penetrans causes infection; however, the Tunga trimamillata flea can result in disease as well. The infestation is also known as chique, chica, nigua, sand flea, bicho do pé, and puce chique.

Tungiasis is endemic in sub-Saharan Africa, India, the Caribbean, and Central and South America. It is usually acquired while walking barefoot on sand or in shady areas near rotting vegetation. Children are at higher risk (peak age of incidence is 5-10 years), and boys are at slightly higher risk than girls. Risk factors include not wearing closed-toe footwear, poverty, and proximity to domestic or wild animal reservoirs (as fleas may exist on these animals).

Because the flea cannot jump very high, involved sites are usually limited to the feet, especially periungually. However, in small children, ectopic sites above the waist are not uncommon.

Tungiasis initially presents as red or brown macules that become nontender papules around the toenails within 24 hours of exposure. Each papule contains a flea. Within a week, the flea matures and swells to a diameter of 1 cm and may harbor up to 200 ova. The site becomes painful after 2-3 days as this engorgement occurs.

If left untreated, the site becomes very pruritic, causing the host to scratch at the lesions, which results in rupture of the flea and dissemination of eggs. The lesions then become desiccated and may leave small scars.