Tunga penetrants

Chigoe or sand flea (the smallest flea)
Lives in warm, sandy soils, often near animals (such as pigsties or stables)
Endemic in Latin America, the Carribean, and sub-Saharan Africa
Pregnant female invades the soft epidermis
Remains embedded for up to 5 weeks, enlarging with time, and eventually the uterus pops out of skin
Pruritic lesion
Treatment is to excise it carefully
Prevention is to wear shoes, or to put DEET on feet