Furuncular myiasis is a skin lesion that is caused by a fly larva growing under the skin. The lesion will often look like a boil or a pimple. The two types of fly larvae known to cause furuncular myiasis are the Cayor worm and human botfly larvae. These flies live in sub-Saharan and tropical Africa and in Latin America. When the adult flies bite a human, they deposit eggs on the skin or nearby clothing. When the eggs come into contact with human skin, they hatch and burrow into the skin. The larvae develop and later emerge from the skin. Signs of infections usually begin 10 to 15 after the eggs have hatched.
A furuncle, or pimple, begins as a small, red bump that grows on the surface of the skin. Sometimes, there is a hole or ulcer in the middle of the bump. Symptoms include itching, a feeling of movement around the affected area, and sometimes sharp pain at the site of the furuncle. Often, botfly bites that lead to furuncular myiasis occur in the scalp.
Diagnosis of furuncular myiasis can be made using a physical examination. Treatment may include medication and cutting off the oxygen supply of the larva by applying a cover over the furuncle. Without oxygen, the larvae may come closer to the skin surface where they can be more easily removed. If left untreated, the larvae will eventually mature and exit the skin. If you have been diagnosed with furuncular myiasis, talk to your doctor about the most current treatment options.