Loa loa filariasis, (Loiasis) is a skin and eye disease caused by the nematode worm Loa loa. Humans contract this disease through the bite of a deer fly (Chrysops spp.) or mango fly, the vectors for Loa loa. The adult Loa loa filarial worm can reach from three to seven centimetres long and 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 vision but can be painful

Must see: 15cm-long worm being removed from a man's eye