Loa loa filariasis (also known as loiasis, loaiasis, Calabar swellings, Fugitive swelling, Tropical swelling and African eyeworm) is a skin and eye disease caused by the nematode worm, loa loa. Humans contract this disease through the bite of a Deer fly or Mango fly (Chrysops spp), the vectors for Loa loa. The adult Loa loa filarial worm migrates throughout the subcutaneous tissues of humans, occasionally crossing into subconjunctival tissues of the eye where it can be easily observed. Loa loa does not normally affect one's vision but can be painful when moving about the eyeball or across the bridge of the nose.The disease can cause red itchy swellings below the skin called "Calabar swellings". The disease is treated with the drug diethylcarbamazine (DEC), and when appropriate, surgical methods may be employed to remove adult worms from the conjunctiva.