External ophthalmomyiasis, a disease established in Hawaii

External ophthalmomyiasis, usually caused by the sheep nasal bot fly, Oestrus ovis L., is characteristically a benign disorder in humans, but may rarely cause severe complications. It occurs on most of the inhabited Hawaiian islands, and is more common than indicated by previously published reports. A typical case is presented along with the fly's life cycle, clinical features, and management.